diff --git a/Include/modsupport.h b/Include/modsupport.h
index ed24b2b311a..f17060c2e1e 100644
--- a/Include/modsupport.h
+++ b/Include/modsupport.h
@@ -66,7 +66,12 @@ PyAPI_FUNC(int) _PyArg_NoPositional(const char *funcname, PyObject *args);
 #define _PyArg_NoPositional(funcname, args) \
     ((args) == NULL || _PyArg_NoPositional((funcname), (args)))
 
-PyAPI_FUNC(void) _PyArg_BadArgument(const char *, const char *, PyObject *);
+PyAPI_FUNC(void) _PyArg_BadArgument(const char *, int, const char *, PyObject *);
+PyAPI_FUNC(int) _PyArg_CheckPositional(const char *, Py_ssize_t,
+                                       Py_ssize_t, Py_ssize_t);
+#define _PyArg_CheckPositional(funcname, nargs, min, max) \
+    (((min) <= (nargs) && (nargs) <= (max)) \
+     || _PyArg_CheckPositional((funcname), (nargs), (min), (max)))
 
 #endif
 
diff --git a/Lib/test/clinic.test b/Lib/test/clinic.test
index 03571a86b7d..7ae8f9642e8 100644
--- a/Lib/test/clinic.test
+++ b/Lib/test/clinic.test
@@ -35,10 +35,19 @@ test_object_converter(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *c;
     PyUnicode_Object *d;
 
-    if (!_PyArg_ParseStack(args, nargs, "OO&O!O:test_object_converter",
-        &a, PyUnicode_FSConverter, &b, &PyUnicode_Type, &c, &d)) {
+    if (!_PyArg_CheckPositional("test_object_converter", nargs, 4, 4)) {
         goto exit;
     }
+    a = args[0];
+    if (!PyUnicode_FSConverter(args[1], &b)) {
+        goto exit;
+    }
+    if (!PyUnicode_Check(args[2])) {
+        _PyArg_BadArgument("test_object_converter", 3, "str", args[2]);
+        goto exit;
+    }
+    c = args[2];
+    d = (PyUnicode_Object *)args[3];
     return_value = test_object_converter_impl(module, a, b, c, d);
 
 exit:
@@ -48,7 +57,7 @@ exit:
 static PyObject *
 test_object_converter_impl(PyObject *module, PyObject *a, PyObject *b,
                            PyObject *c, PyUnicode_Object *d)
-/*[clinic end generated code: output=ac25517226de46c8 input=005e6a8a711a869b]*/
+/*[clinic end generated code: output=f2c26174b3d46e94 input=005e6a8a711a869b]*/
 
 /*[clinic input]
 test_object_converter_one_arg
@@ -159,10 +168,59 @@ test_object_converter_subclass_of(PyObject *module, PyObject *const *args, Py_ss
     PyObject *i;
     PyObject *j;
 
-    if (!_PyArg_ParseStack(args, nargs, "O!O!O!O!O!O!O!O!O!O!:test_object_converter_subclass_of",
-        &PyLong_Type, &a, &PyTuple_Type, &b, &PyList_Type, &c, &PySet_Type, &d, &PyFrozenSet_Type, &e, &PyDict_Type, &f, &PyUnicode_Type, &g, &PyBytes_Type, &h, &PyByteArray_Type, &i, &MyType, &j)) {
+    if (!_PyArg_CheckPositional("test_object_converter_subclass_of", nargs, 10, 10)) {
         goto exit;
     }
+    if (!PyLong_Check(args[0])) {
+        _PyArg_BadArgument("test_object_converter_subclass_of", 1, "int", args[0]);
+        goto exit;
+    }
+    a = args[0];
+    if (!PyTuple_Check(args[1])) {
+        _PyArg_BadArgument("test_object_converter_subclass_of", 2, "tuple", args[1]);
+        goto exit;
+    }
+    b = args[1];
+    if (!PyList_Check(args[2])) {
+        _PyArg_BadArgument("test_object_converter_subclass_of", 3, "list", args[2]);
+        goto exit;
+    }
+    c = args[2];
+    if (!PySet_Check(args[3])) {
+        _PyArg_BadArgument("test_object_converter_subclass_of", 4, "set", args[3]);
+        goto exit;
+    }
+    d = args[3];
+    if (!PyFrozenSet_Check(args[4])) {
+        _PyArg_BadArgument("test_object_converter_subclass_of", 5, "frozenset", args[4]);
+        goto exit;
+    }
+    e = args[4];
+    if (!PyDict_Check(args[5])) {
+        _PyArg_BadArgument("test_object_converter_subclass_of", 6, "dict", args[5]);
+        goto exit;
+    }
+    f = args[5];
+    if (!PyUnicode_Check(args[6])) {
+        _PyArg_BadArgument("test_object_converter_subclass_of", 7, "str", args[6]);
+        goto exit;
+    }
+    g = args[6];
+    if (!PyBytes_Check(args[7])) {
+        _PyArg_BadArgument("test_object_converter_subclass_of", 8, "bytes", args[7]);
+        goto exit;
+    }
+    h = args[7];
+    if (!PyByteArray_Check(args[8])) {
+        _PyArg_BadArgument("test_object_converter_subclass_of", 9, "bytearray", args[8]);
+        goto exit;
+    }
+    i = args[8];
+    if (!PyObject_TypeCheck(args[9], &MyType)) {
+        _PyArg_BadArgument("test_object_converter_subclass_of", 10, (&MyType)->tp_name, args[9]);
+        goto exit;
+    }
+    j = args[9];
     return_value = test_object_converter_subclass_of_impl(module, a, b, c, d, e, f, g, h, i, j);
 
 exit:
@@ -174,7 +232,7 @@ test_object_converter_subclass_of_impl(PyObject *module, PyObject *a,
                                        PyObject *b, PyObject *c, PyObject *d,
                                        PyObject *e, PyObject *f, PyObject *g,
                                        PyObject *h, PyObject *i, PyObject *j)
-/*[clinic end generated code: output=b26bcdc31dfc7872 input=31b06b772d5f983e]*/
+/*[clinic end generated code: output=99691bda8eeda6d6 input=31b06b772d5f983e]*/
 
 /*[clinic input]
 test_PyBytesObject_converter
@@ -202,7 +260,7 @@ test_PyBytesObject_converter(PyObject *module, PyObject *arg)
     PyBytesObject *a;
 
     if (!PyBytes_Check(arg)) {
-        _PyArg_BadArgument("test_PyBytesObject_converter", "bytes", arg);
+        _PyArg_BadArgument("test_PyBytesObject_converter", 0, "bytes", arg);
         goto exit;
     }
     a = (PyBytesObject *)arg;
@@ -214,7 +272,7 @@ exit:
 
 static PyObject *
 test_PyBytesObject_converter_impl(PyObject *module, PyBytesObject *a)
-/*[clinic end generated code: output=fd69d6df4d26c853 input=12b10c7cb5750400]*/
+/*[clinic end generated code: output=5d9a301c1df24eb5 input=12b10c7cb5750400]*/
 
 /*[clinic input]
 test_PyByteArrayObject_converter
@@ -242,7 +300,7 @@ test_PyByteArrayObject_converter(PyObject *module, PyObject *arg)
     PyByteArrayObject *a;
 
     if (!PyByteArray_Check(arg)) {
-        _PyArg_BadArgument("test_PyByteArrayObject_converter", "bytearray", arg);
+        _PyArg_BadArgument("test_PyByteArrayObject_converter", 0, "bytearray", arg);
         goto exit;
     }
     a = (PyByteArrayObject *)arg;
@@ -254,7 +312,7 @@ exit:
 
 static PyObject *
 test_PyByteArrayObject_converter_impl(PyObject *module, PyByteArrayObject *a)
-/*[clinic end generated code: output=d309c909182c4183 input=5a657da535d194ae]*/
+/*[clinic end generated code: output=9455d06f4f09637b input=5a657da535d194ae]*/
 
 /*[clinic input]
 test_unicode_converter
@@ -282,7 +340,7 @@ test_unicode_converter(PyObject *module, PyObject *arg)
     PyObject *a;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("test_unicode_converter", "str", arg);
+        _PyArg_BadArgument("test_unicode_converter", 0, "str", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg) == -1) {
@@ -297,7 +355,7 @@ exit:
 
 static PyObject *
 test_unicode_converter_impl(PyObject *module, PyObject *a)
-/*[clinic end generated code: output=ca603454e1f8f764 input=aa33612df92aa9c5]*/
+/*[clinic end generated code: output=9275c04fe204f4c5 input=aa33612df92aa9c5]*/
 
 /*[clinic input]
 test_bool_converter
@@ -328,10 +386,36 @@ test_bool_converter(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int b = 1;
     int c = 1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|ppi:test_bool_converter",
-        &a, &b, &c)) {
+    if (!_PyArg_CheckPositional("test_bool_converter", nargs, 0, 3)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    a = PyObject_IsTrue(args[0]);
+    if (a < 0) {
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    b = PyObject_IsTrue(args[1]);
+    if (b < 0) {
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    c = _PyLong_AsInt(args[2]);
+    if (c == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = test_bool_converter_impl(module, a, b, c);
 
 exit:
@@ -340,7 +424,7 @@ exit:
 
 static PyObject *
 test_bool_converter_impl(PyObject *module, int a, int b, int c)
-/*[clinic end generated code: output=f08a22d3390ab6f7 input=939854fa9f248c60]*/
+/*[clinic end generated code: output=25f20963894256a1 input=939854fa9f248c60]*/
 
 /*[clinic input]
 test_char_converter
@@ -397,10 +481,192 @@ test_char_converter(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     char m = '\x00';
     char n = '\xff';
 
-    if (!_PyArg_ParseStack(args, nargs, "|cccccccccccccc:test_char_converter",
-        &a, &b, &c, &d, &e, &f, &g, &h, &i, &j, &k, &l, &m, &n)) {
+    if (!_PyArg_CheckPositional("test_char_converter", nargs, 0, 14)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyBytes_Check(args[0]) && PyBytes_GET_SIZE(args[0]) == 1) {
+        a = PyBytes_AS_STRING(args[0])[0];
+    }
+    else if (PyByteArray_Check(args[0]) && PyByteArray_GET_SIZE(args[0]) == 1) {
+        a = PyByteArray_AS_STRING(args[0])[0];
+    }
+    else {
+        _PyArg_BadArgument("test_char_converter", 1, "a byte string of length 1", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyBytes_Check(args[1]) && PyBytes_GET_SIZE(args[1]) == 1) {
+        b = PyBytes_AS_STRING(args[1])[0];
+    }
+    else if (PyByteArray_Check(args[1]) && PyByteArray_GET_SIZE(args[1]) == 1) {
+        b = PyByteArray_AS_STRING(args[1])[0];
+    }
+    else {
+        _PyArg_BadArgument("test_char_converter", 2, "a byte string of length 1", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyBytes_Check(args[2]) && PyBytes_GET_SIZE(args[2]) == 1) {
+        c = PyBytes_AS_STRING(args[2])[0];
+    }
+    else if (PyByteArray_Check(args[2]) && PyByteArray_GET_SIZE(args[2]) == 1) {
+        c = PyByteArray_AS_STRING(args[2])[0];
+    }
+    else {
+        _PyArg_BadArgument("test_char_converter", 3, "a byte string of length 1", args[2]);
+        goto exit;
+    }
+    if (nargs < 4) {
+        goto skip_optional;
+    }
+    if (PyBytes_Check(args[3]) && PyBytes_GET_SIZE(args[3]) == 1) {
+        d = PyBytes_AS_STRING(args[3])[0];
+    }
+    else if (PyByteArray_Check(args[3]) && PyByteArray_GET_SIZE(args[3]) == 1) {
+        d = PyByteArray_AS_STRING(args[3])[0];
+    }
+    else {
+        _PyArg_BadArgument("test_char_converter", 4, "a byte string of length 1", args[3]);
+        goto exit;
+    }
+    if (nargs < 5) {
+        goto skip_optional;
+    }
+    if (PyBytes_Check(args[4]) && PyBytes_GET_SIZE(args[4]) == 1) {
+        e = PyBytes_AS_STRING(args[4])[0];
+    }
+    else if (PyByteArray_Check(args[4]) && PyByteArray_GET_SIZE(args[4]) == 1) {
+        e = PyByteArray_AS_STRING(args[4])[0];
+    }
+    else {
+        _PyArg_BadArgument("test_char_converter", 5, "a byte string of length 1", args[4]);
+        goto exit;
+    }
+    if (nargs < 6) {
+        goto skip_optional;
+    }
+    if (PyBytes_Check(args[5]) && PyBytes_GET_SIZE(args[5]) == 1) {
+        f = PyBytes_AS_STRING(args[5])[0];
+    }
+    else if (PyByteArray_Check(args[5]) && PyByteArray_GET_SIZE(args[5]) == 1) {
+        f = PyByteArray_AS_STRING(args[5])[0];
+    }
+    else {
+        _PyArg_BadArgument("test_char_converter", 6, "a byte string of length 1", args[5]);
+        goto exit;
+    }
+    if (nargs < 7) {
+        goto skip_optional;
+    }
+    if (PyBytes_Check(args[6]) && PyBytes_GET_SIZE(args[6]) == 1) {
+        g = PyBytes_AS_STRING(args[6])[0];
+    }
+    else if (PyByteArray_Check(args[6]) && PyByteArray_GET_SIZE(args[6]) == 1) {
+        g = PyByteArray_AS_STRING(args[6])[0];
+    }
+    else {
+        _PyArg_BadArgument("test_char_converter", 7, "a byte string of length 1", args[6]);
+        goto exit;
+    }
+    if (nargs < 8) {
+        goto skip_optional;
+    }
+    if (PyBytes_Check(args[7]) && PyBytes_GET_SIZE(args[7]) == 1) {
+        h = PyBytes_AS_STRING(args[7])[0];
+    }
+    else if (PyByteArray_Check(args[7]) && PyByteArray_GET_SIZE(args[7]) == 1) {
+        h = PyByteArray_AS_STRING(args[7])[0];
+    }
+    else {
+        _PyArg_BadArgument("test_char_converter", 8, "a byte string of length 1", args[7]);
+        goto exit;
+    }
+    if (nargs < 9) {
+        goto skip_optional;
+    }
+    if (PyBytes_Check(args[8]) && PyBytes_GET_SIZE(args[8]) == 1) {
+        i = PyBytes_AS_STRING(args[8])[0];
+    }
+    else if (PyByteArray_Check(args[8]) && PyByteArray_GET_SIZE(args[8]) == 1) {
+        i = PyByteArray_AS_STRING(args[8])[0];
+    }
+    else {
+        _PyArg_BadArgument("test_char_converter", 9, "a byte string of length 1", args[8]);
+        goto exit;
+    }
+    if (nargs < 10) {
+        goto skip_optional;
+    }
+    if (PyBytes_Check(args[9]) && PyBytes_GET_SIZE(args[9]) == 1) {
+        j = PyBytes_AS_STRING(args[9])[0];
+    }
+    else if (PyByteArray_Check(args[9]) && PyByteArray_GET_SIZE(args[9]) == 1) {
+        j = PyByteArray_AS_STRING(args[9])[0];
+    }
+    else {
+        _PyArg_BadArgument("test_char_converter", 10, "a byte string of length 1", args[9]);
+        goto exit;
+    }
+    if (nargs < 11) {
+        goto skip_optional;
+    }
+    if (PyBytes_Check(args[10]) && PyBytes_GET_SIZE(args[10]) == 1) {
+        k = PyBytes_AS_STRING(args[10])[0];
+    }
+    else if (PyByteArray_Check(args[10]) && PyByteArray_GET_SIZE(args[10]) == 1) {
+        k = PyByteArray_AS_STRING(args[10])[0];
+    }
+    else {
+        _PyArg_BadArgument("test_char_converter", 11, "a byte string of length 1", args[10]);
+        goto exit;
+    }
+    if (nargs < 12) {
+        goto skip_optional;
+    }
+    if (PyBytes_Check(args[11]) && PyBytes_GET_SIZE(args[11]) == 1) {
+        l = PyBytes_AS_STRING(args[11])[0];
+    }
+    else if (PyByteArray_Check(args[11]) && PyByteArray_GET_SIZE(args[11]) == 1) {
+        l = PyByteArray_AS_STRING(args[11])[0];
+    }
+    else {
+        _PyArg_BadArgument("test_char_converter", 12, "a byte string of length 1", args[11]);
+        goto exit;
+    }
+    if (nargs < 13) {
+        goto skip_optional;
+    }
+    if (PyBytes_Check(args[12]) && PyBytes_GET_SIZE(args[12]) == 1) {
+        m = PyBytes_AS_STRING(args[12])[0];
+    }
+    else if (PyByteArray_Check(args[12]) && PyByteArray_GET_SIZE(args[12]) == 1) {
+        m = PyByteArray_AS_STRING(args[12])[0];
+    }
+    else {
+        _PyArg_BadArgument("test_char_converter", 13, "a byte string of length 1", args[12]);
+        goto exit;
+    }
+    if (nargs < 14) {
+        goto skip_optional;
+    }
+    if (PyBytes_Check(args[13]) && PyBytes_GET_SIZE(args[13]) == 1) {
+        n = PyBytes_AS_STRING(args[13])[0];
+    }
+    else if (PyByteArray_Check(args[13]) && PyByteArray_GET_SIZE(args[13]) == 1) {
+        n = PyByteArray_AS_STRING(args[13])[0];
+    }
+    else {
+        _PyArg_BadArgument("test_char_converter", 14, "a byte string of length 1", args[13]);
+        goto exit;
+    }
+skip_optional:
     return_value = test_char_converter_impl(module, a, b, c, d, e, f, g, h, i, j, k, l, m, n);
 
 exit:
@@ -411,7 +677,7 @@ static PyObject *
 test_char_converter_impl(PyObject *module, char a, char b, char c, char d,
                          char e, char f, char g, char h, char i, char j,
                          char k, char l, char m, char n)
-/*[clinic end generated code: output=14c61e8ee78f3d47 input=e42330417a44feac]*/
+/*[clinic end generated code: output=e041d687555e0a5d input=e42330417a44feac]*/
 
 /*[clinic input]
 test_unsigned_char_converter
@@ -443,10 +709,81 @@ test_unsigned_char_converter(PyObject *module, PyObject *const *args, Py_ssize_t
     unsigned char b = 34;
     unsigned char c = 56;
 
-    if (!_PyArg_ParseStack(args, nargs, "|bbB:test_unsigned_char_converter",
-        &a, &b, &c)) {
+    if (!_PyArg_CheckPositional("test_unsigned_char_converter", nargs, 0, 3)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        long ival = PyLong_AsLong(args[0]);
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        else if (ival < 0) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "unsigned byte integer is less than minimum");
+            goto exit;
+        }
+        else if (ival > UCHAR_MAX) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "unsigned byte integer is greater than maximum");
+            goto exit;
+        }
+        else {
+            a = (unsigned char) ival;
+        }
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        long ival = PyLong_AsLong(args[1]);
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        else if (ival < 0) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "unsigned byte integer is less than minimum");
+            goto exit;
+        }
+        else if (ival > UCHAR_MAX) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "unsigned byte integer is greater than maximum");
+            goto exit;
+        }
+        else {
+            b = (unsigned char) ival;
+        }
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        long ival = PyLong_AsUnsignedLongMask(args[2]);
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        else {
+            c = (unsigned char) ival;
+        }
+    }
+skip_optional:
     return_value = test_unsigned_char_converter_impl(module, a, b, c);
 
 exit:
@@ -456,7 +793,7 @@ exit:
 static PyObject *
 test_unsigned_char_converter_impl(PyObject *module, unsigned char a,
                                   unsigned char b, unsigned char c)
-/*[clinic end generated code: output=a4fd7ad26077dcfc input=021414060993e289]*/
+/*[clinic end generated code: output=ebf905c5c9414762 input=021414060993e289]*/
 
 /*[clinic input]
 test_short_converter
@@ -483,10 +820,37 @@ test_short_converter(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     short a = 12;
 
-    if (!_PyArg_ParseStack(args, nargs, "|h:test_short_converter",
-        &a)) {
+    if (!_PyArg_CheckPositional("test_short_converter", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        long ival = PyLong_AsLong(args[0]);
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        else if (ival < SHRT_MIN) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "signed short integer is less than minimum");
+            goto exit;
+        }
+        else if (ival > SHRT_MAX) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "signed short integer is greater than maximum");
+            goto exit;
+        }
+        else {
+            a = (short) ival;
+        }
+    }
+skip_optional:
     return_value = test_short_converter_impl(module, a);
 
 exit:
@@ -495,7 +859,7 @@ exit:
 
 static PyObject *
 test_short_converter_impl(PyObject *module, short a)
-/*[clinic end generated code: output=08259a92c12890b1 input=6a8a7a509a498ff4]*/
+/*[clinic end generated code: output=86fe1a1496a7ff20 input=6a8a7a509a498ff4]*/
 
 /*[clinic input]
 test_unsigned_short_converter
@@ -527,10 +891,34 @@ test_unsigned_short_converter(PyObject *module, PyObject *const *args, Py_ssize_
     unsigned short b = 34;
     unsigned short c = 56;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&O&H:test_unsigned_short_converter",
-        _PyLong_UnsignedShort_Converter, &a, _PyLong_UnsignedShort_Converter, &b, &c)) {
+    if (!_PyArg_CheckPositional("test_unsigned_short_converter", nargs, 0, 3)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_PyLong_UnsignedShort_Converter(args[0], &a)) {
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!_PyLong_UnsignedShort_Converter(args[1], &b)) {
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    c = (unsigned short)PyLong_AsUnsignedLongMask(args[2]);
+    if (c == (unsigned short)-1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = test_unsigned_short_converter_impl(module, a, b, c);
 
 exit:
@@ -540,7 +928,7 @@ exit:
 static PyObject *
 test_unsigned_short_converter_impl(PyObject *module, unsigned short a,
                                    unsigned short b, unsigned short c)
-/*[clinic end generated code: output=d714bceb98c1fe84 input=cdfd8eff3d9176b4]*/
+/*[clinic end generated code: output=3779fe104319e3ae input=cdfd8eff3d9176b4]*/
 
 /*[clinic input]
 test_int_converter
@@ -573,10 +961,61 @@ test_int_converter(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int c = 45;
     myenum d = 67;
 
-    if (!_PyArg_ParseStack(args, nargs, "|iiCi:test_int_converter",
-        &a, &b, &c, &d)) {
+    if (!_PyArg_CheckPositional("test_int_converter", nargs, 0, 4)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    a = _PyLong_AsInt(args[0]);
+    if (a == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    b = _PyLong_AsInt(args[1]);
+    if (b == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (!PyUnicode_Check(args[2])) {
+        _PyArg_BadArgument("test_int_converter", 3, "a unicode character", args[2]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[2])) {
+        goto exit;
+    }
+    if (PyUnicode_GET_LENGTH(args[2]) != 1) {
+        _PyArg_BadArgument("test_int_converter", 3, "a unicode character", args[2]);
+        goto exit;
+    }
+    c = PyUnicode_READ_CHAR(args[2], 0);
+    if (nargs < 4) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[3])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    d = _PyLong_AsInt(args[3]);
+    if (d == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = test_int_converter_impl(module, a, b, c, d);
 
 exit:
@@ -585,7 +1024,7 @@ exit:
 
 static PyObject *
 test_int_converter_impl(PyObject *module, int a, int b, int c, myenum d)
-/*[clinic end generated code: output=1995799d5264e4a5 input=d20541fc1ca0553e]*/
+/*[clinic end generated code: output=de74e24e85a669a5 input=d20541fc1ca0553e]*/
 
 /*[clinic input]
 test_unsigned_int_converter
@@ -617,10 +1056,34 @@ test_unsigned_int_converter(PyObject *module, PyObject *const *args, Py_ssize_t
     unsigned int b = 34;
     unsigned int c = 56;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&O&I:test_unsigned_int_converter",
-        _PyLong_UnsignedInt_Converter, &a, _PyLong_UnsignedInt_Converter, &b, &c)) {
+    if (!_PyArg_CheckPositional("test_unsigned_int_converter", nargs, 0, 3)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_PyLong_UnsignedInt_Converter(args[0], &a)) {
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!_PyLong_UnsignedInt_Converter(args[1], &b)) {
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    c = (unsigned int)PyLong_AsUnsignedLongMask(args[2]);
+    if (c == (unsigned int)-1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = test_unsigned_int_converter_impl(module, a, b, c);
 
 exit:
@@ -630,7 +1093,7 @@ exit:
 static PyObject *
 test_unsigned_int_converter_impl(PyObject *module, unsigned int a,
                                  unsigned int b, unsigned int c)
-/*[clinic end generated code: output=3cdb7a3ef2b369a3 input=5533534828b62fc0]*/
+/*[clinic end generated code: output=189176ce67c7d2e7 input=5533534828b62fc0]*/
 
 /*[clinic input]
 test_long_converter
@@ -657,10 +1120,22 @@ test_long_converter(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     long a = 12;
 
-    if (!_PyArg_ParseStack(args, nargs, "|l:test_long_converter",
-        &a)) {
+    if (!_PyArg_CheckPositional("test_long_converter", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    a = PyLong_AsLong(args[0]);
+    if (a == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = test_long_converter_impl(module, a);
 
 exit:
@@ -669,7 +1144,7 @@ exit:
 
 static PyObject *
 test_long_converter_impl(PyObject *module, long a)
-/*[clinic end generated code: output=65a8092a1dc10de6 input=d2179e3c9cdcde89]*/
+/*[clinic end generated code: output=44cd8823f59d116b input=d2179e3c9cdcde89]*/
 
 /*[clinic input]
 test_unsigned_long_converter
@@ -701,10 +1176,30 @@ test_unsigned_long_converter(PyObject *module, PyObject *const *args, Py_ssize_t
     unsigned long b = 34;
     unsigned long c = 56;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&O&k:test_unsigned_long_converter",
-        _PyLong_UnsignedLong_Converter, &a, _PyLong_UnsignedLong_Converter, &b, &c)) {
+    if (!_PyArg_CheckPositional("test_unsigned_long_converter", nargs, 0, 3)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_PyLong_UnsignedLong_Converter(args[0], &a)) {
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!_PyLong_UnsignedLong_Converter(args[1], &b)) {
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (!PyLong_Check(args[2])) {
+        _PyArg_BadArgument("test_unsigned_long_converter", 3, "int", args[2]);
+        goto exit;
+    }
+    c = PyLong_AsUnsignedLongMask(args[2]);
+skip_optional:
     return_value = test_unsigned_long_converter_impl(module, a, b, c);
 
 exit:
@@ -714,7 +1209,7 @@ exit:
 static PyObject *
 test_unsigned_long_converter_impl(PyObject *module, unsigned long a,
                                   unsigned long b, unsigned long c)
-/*[clinic end generated code: output=81fd66d8981abeb2 input=f450d94cae1ef73b]*/
+/*[clinic end generated code: output=1c05c871c0309e08 input=f450d94cae1ef73b]*/
 
 /*[clinic input]
 test_long_long_converter
@@ -741,10 +1236,22 @@ test_long_long_converter(PyObject *module, PyObject *const *args, Py_ssize_t nar
     PyObject *return_value = NULL;
     long long a = 12;
 
-    if (!_PyArg_ParseStack(args, nargs, "|L:test_long_long_converter",
-        &a)) {
+    if (!_PyArg_CheckPositional("test_long_long_converter", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    a = PyLong_AsLongLong(args[0]);
+    if (a == (PY_LONG_LONG)-1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = test_long_long_converter_impl(module, a);
 
 exit:
@@ -753,7 +1260,7 @@ exit:
 
 static PyObject *
 test_long_long_converter_impl(PyObject *module, long long a)
-/*[clinic end generated code: output=9412f5800661b0c0 input=d5fc81577ff4dd02]*/
+/*[clinic end generated code: output=3e8083f3aee4f18a input=d5fc81577ff4dd02]*/
 
 /*[clinic input]
 test_unsigned_long_long_converter
@@ -787,10 +1294,30 @@ test_unsigned_long_long_converter(PyObject *module, PyObject *const *args, Py_ss
     unsigned long long b = 34;
     unsigned long long c = 56;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&O&K:test_unsigned_long_long_converter",
-        _PyLong_UnsignedLongLong_Converter, &a, _PyLong_UnsignedLongLong_Converter, &b, &c)) {
+    if (!_PyArg_CheckPositional("test_unsigned_long_long_converter", nargs, 0, 3)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_PyLong_UnsignedLongLong_Converter(args[0], &a)) {
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!_PyLong_UnsignedLongLong_Converter(args[1], &b)) {
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (!PyLong_Check(args[2])) {
+        _PyArg_BadArgument("test_unsigned_long_long_converter", 3, "int", args[2]);
+        goto exit;
+    }
+    c = PyLong_AsUnsignedLongLongMask(args[2]);
+skip_optional:
     return_value = test_unsigned_long_long_converter_impl(module, a, b, c);
 
 exit:
@@ -802,7 +1329,7 @@ test_unsigned_long_long_converter_impl(PyObject *module,
                                        unsigned long long a,
                                        unsigned long long b,
                                        unsigned long long c)
-/*[clinic end generated code: output=f5a57e0ccc048a32 input=a15115dc41866ff4]*/
+/*[clinic end generated code: output=0a9b17fb824e28eb input=a15115dc41866ff4]*/
 
 /*[clinic input]
 test_Py_ssize_t_converter
@@ -834,10 +1361,56 @@ test_Py_ssize_t_converter(PyObject *module, PyObject *const *args, Py_ssize_t na
     Py_ssize_t b = 34;
     Py_ssize_t c = 56;
 
-    if (!_PyArg_ParseStack(args, nargs, "|nnO&:test_Py_ssize_t_converter",
-        &a, &b, _Py_convert_optional_to_ssize_t, &c)) {
+    if (!_PyArg_CheckPositional("test_Py_ssize_t_converter", nargs, 0, 3)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        a = ival;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[1]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        b = ival;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (!_Py_convert_optional_to_ssize_t(args[2], &c)) {
+        goto exit;
+    }
+skip_optional:
     return_value = test_Py_ssize_t_converter_impl(module, a, b, c);
 
 exit:
@@ -847,7 +1420,7 @@ exit:
 static PyObject *
 test_Py_ssize_t_converter_impl(PyObject *module, Py_ssize_t a, Py_ssize_t b,
                                Py_ssize_t c)
-/*[clinic end generated code: output=50bc360c57b40e3f input=3855f184bb3f299d]*/
+/*[clinic end generated code: output=a46d2aaf40c10398 input=3855f184bb3f299d]*/
 
 /*[clinic input]
 test_slice_index_converter
@@ -879,10 +1452,28 @@ test_slice_index_converter(PyObject *module, PyObject *const *args, Py_ssize_t n
     Py_ssize_t b = 34;
     Py_ssize_t c = 56;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&O&O&:test_slice_index_converter",
-        _PyEval_SliceIndex, &a, _PyEval_SliceIndexNotNone, &b, _PyEval_SliceIndex, &c)) {
+    if (!_PyArg_CheckPositional("test_slice_index_converter", nargs, 0, 3)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_PyEval_SliceIndex(args[0], &a)) {
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!_PyEval_SliceIndexNotNone(args[1], &b)) {
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (!_PyEval_SliceIndex(args[2], &c)) {
+        goto exit;
+    }
+skip_optional:
     return_value = test_slice_index_converter_impl(module, a, b, c);
 
 exit:
@@ -892,7 +1483,7 @@ exit:
 static PyObject *
 test_slice_index_converter_impl(PyObject *module, Py_ssize_t a, Py_ssize_t b,
                                 Py_ssize_t c)
-/*[clinic end generated code: output=33b9152bf3c5963a input=edeadb0ee126f531]*/
+/*[clinic end generated code: output=2148703cd3c6e941 input=edeadb0ee126f531]*/
 
 /*[clinic input]
 test_size_t_converter
@@ -919,10 +1510,16 @@ test_size_t_converter(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     size_t a = 12;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&:test_size_t_converter",
-        _PyLong_Size_t_Converter, &a)) {
+    if (!_PyArg_CheckPositional("test_size_t_converter", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_PyLong_Size_t_Converter(args[0], &a)) {
+        goto exit;
+    }
+skip_optional:
     return_value = test_size_t_converter_impl(module, a);
 
 exit:
@@ -931,7 +1528,7 @@ exit:
 
 static PyObject *
 test_size_t_converter_impl(PyObject *module, size_t a)
-/*[clinic end generated code: output=02fe6bf4c5a139d5 input=52e93a0fed0f1fb3]*/
+/*[clinic end generated code: output=8a91a9ca8a92dabb input=52e93a0fed0f1fb3]*/
 
 /*[clinic input]
 test_float_converter
@@ -958,10 +1555,17 @@ test_float_converter(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     float a = 12.5;
 
-    if (!_PyArg_ParseStack(args, nargs, "|f:test_float_converter",
-        &a)) {
+    if (!_PyArg_CheckPositional("test_float_converter", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    a = (float) PyFloat_AsDouble(args[0]);
+    if (PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = test_float_converter_impl(module, a);
 
 exit:
@@ -970,7 +1574,7 @@ exit:
 
 static PyObject *
 test_float_converter_impl(PyObject *module, float a)
-/*[clinic end generated code: output=a0689b5ee76673ad input=259c0d98eca35034]*/
+/*[clinic end generated code: output=8293566b2ec1fc52 input=259c0d98eca35034]*/
 
 /*[clinic input]
 test_double_converter
@@ -997,10 +1601,17 @@ test_double_converter(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     double a = 12.5;
 
-    if (!_PyArg_ParseStack(args, nargs, "|d:test_double_converter",
-        &a)) {
+    if (!_PyArg_CheckPositional("test_double_converter", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    a = PyFloat_AsDouble(args[0]);
+    if (PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = test_double_converter_impl(module, a);
 
 exit:
@@ -1009,7 +1620,7 @@ exit:
 
 static PyObject *
 test_double_converter_impl(PyObject *module, double a)
-/*[clinic end generated code: output=b78d23bd37b40681 input=c6a9945706a41c27]*/
+/*[clinic end generated code: output=487081a9b8da67ab input=c6a9945706a41c27]*/
 
 /*[clinic input]
 test_Py_complex_converter
diff --git a/Modules/_io/clinic/bufferedio.c.h b/Modules/_io/clinic/bufferedio.c.h
index 6569e02012b..6345b9e16e8 100644
--- a/Modules/_io/clinic/bufferedio.c.h
+++ b/Modules/_io/clinic/bufferedio.c.h
@@ -21,11 +21,11 @@ _io__BufferedIOBase_readinto(PyObject *self, PyObject *arg)
 
     if (PyObject_GetBuffer(arg, &buffer, PyBUF_WRITABLE) < 0) {
         PyErr_Clear();
-        _PyArg_BadArgument("readinto", "read-write bytes-like object", arg);
+        _PyArg_BadArgument("readinto", 0, "read-write bytes-like object", arg);
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&buffer, 'C')) {
-        _PyArg_BadArgument("readinto", "contiguous buffer", arg);
+        _PyArg_BadArgument("readinto", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = _io__BufferedIOBase_readinto_impl(self, &buffer);
@@ -58,11 +58,11 @@ _io__BufferedIOBase_readinto1(PyObject *self, PyObject *arg)
 
     if (PyObject_GetBuffer(arg, &buffer, PyBUF_WRITABLE) < 0) {
         PyErr_Clear();
-        _PyArg_BadArgument("readinto1", "read-write bytes-like object", arg);
+        _PyArg_BadArgument("readinto1", 0, "read-write bytes-like object", arg);
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&buffer, 'C')) {
-        _PyArg_BadArgument("readinto1", "contiguous buffer", arg);
+        _PyArg_BadArgument("readinto1", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = _io__BufferedIOBase_readinto1_impl(self, &buffer);
@@ -114,10 +114,30 @@ _io__Buffered_peek(buffered *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t size = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "|n:peek",
-        &size)) {
+    if (!_PyArg_CheckPositional("peek", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        size = ival;
+    }
+skip_optional:
     return_value = _io__Buffered_peek_impl(self, size);
 
 exit:
@@ -141,10 +161,16 @@ _io__Buffered_read(buffered *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t n = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&:read",
-        _Py_convert_optional_to_ssize_t, &n)) {
+    if (!_PyArg_CheckPositional("read", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_Py_convert_optional_to_ssize_t(args[0], &n)) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io__Buffered_read_impl(self, n);
 
 exit:
@@ -168,10 +194,30 @@ _io__Buffered_read1(buffered *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t n = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|n:read1",
-        &n)) {
+    if (!_PyArg_CheckPositional("read1", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        n = ival;
+    }
+skip_optional:
     return_value = _io__Buffered_read1_impl(self, n);
 
 exit:
@@ -197,11 +243,11 @@ _io__Buffered_readinto(buffered *self, PyObject *arg)
 
     if (PyObject_GetBuffer(arg, &buffer, PyBUF_WRITABLE) < 0) {
         PyErr_Clear();
-        _PyArg_BadArgument("readinto", "read-write bytes-like object", arg);
+        _PyArg_BadArgument("readinto", 0, "read-write bytes-like object", arg);
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&buffer, 'C')) {
-        _PyArg_BadArgument("readinto", "contiguous buffer", arg);
+        _PyArg_BadArgument("readinto", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = _io__Buffered_readinto_impl(self, &buffer);
@@ -234,11 +280,11 @@ _io__Buffered_readinto1(buffered *self, PyObject *arg)
 
     if (PyObject_GetBuffer(arg, &buffer, PyBUF_WRITABLE) < 0) {
         PyErr_Clear();
-        _PyArg_BadArgument("readinto1", "read-write bytes-like object", arg);
+        _PyArg_BadArgument("readinto1", 0, "read-write bytes-like object", arg);
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&buffer, 'C')) {
-        _PyArg_BadArgument("readinto1", "contiguous buffer", arg);
+        _PyArg_BadArgument("readinto1", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = _io__Buffered_readinto1_impl(self, &buffer);
@@ -269,10 +315,16 @@ _io__Buffered_readline(buffered *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t size = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&:readline",
-        _Py_convert_optional_to_ssize_t, &size)) {
+    if (!_PyArg_CheckPositional("readline", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_Py_convert_optional_to_ssize_t(args[0], &size)) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io__Buffered_readline_impl(self, size);
 
 exit:
@@ -297,10 +349,23 @@ _io__Buffered_seek(buffered *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *targetobj;
     int whence = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "O|i:seek",
-        &targetobj, &whence)) {
+    if (!_PyArg_CheckPositional("seek", nargs, 1, 2)) {
         goto exit;
     }
+    targetobj = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    whence = _PyLong_AsInt(args[1]);
+    if (whence == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io__Buffered_seek_impl(self, targetobj, whence);
 
 exit:
@@ -418,7 +483,7 @@ _io_BufferedWriter_write(buffered *self, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&buffer, 'C')) {
-        _PyArg_BadArgument("write", "contiguous buffer", arg);
+        _PyArg_BadArgument("write", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = _io_BufferedWriter_write_impl(self, &buffer);
@@ -462,10 +527,32 @@ _io_BufferedRWPair___init__(PyObject *self, PyObject *args, PyObject *kwargs)
         !_PyArg_NoKeywords("BufferedRWPair", kwargs)) {
         goto exit;
     }
-    if (!PyArg_ParseTuple(args, "OO|n:BufferedRWPair",
-        &reader, &writer, &buffer_size)) {
+    if (!_PyArg_CheckPositional("BufferedRWPair", PyTuple_GET_SIZE(args), 2, 3)) {
         goto exit;
     }
+    reader = PyTuple_GET_ITEM(args, 0);
+    writer = PyTuple_GET_ITEM(args, 1);
+    if (PyTuple_GET_SIZE(args) < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(PyTuple_GET_ITEM(args, 2))) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(PyTuple_GET_ITEM(args, 2));
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        buffer_size = ival;
+    }
+skip_optional:
     return_value = _io_BufferedRWPair___init___impl((rwpair *)self, reader, writer, buffer_size);
 
 exit:
@@ -504,4 +591,4 @@ _io_BufferedRandom___init__(PyObject *self, PyObject *args, PyObject *kwargs)
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=40de95d461a20782 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=a85f61f495feff5c input=a9049054013a1b77]*/
diff --git a/Modules/_io/clinic/bytesio.c.h b/Modules/_io/clinic/bytesio.c.h
index 07c8866126e..558841697b3 100644
--- a/Modules/_io/clinic/bytesio.c.h
+++ b/Modules/_io/clinic/bytesio.c.h
@@ -169,10 +169,16 @@ _io_BytesIO_read(bytesio *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t size = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&:read",
-        _Py_convert_optional_to_ssize_t, &size)) {
+    if (!_PyArg_CheckPositional("read", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_Py_convert_optional_to_ssize_t(args[0], &size)) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io_BytesIO_read_impl(self, size);
 
 exit:
@@ -200,10 +206,16 @@ _io_BytesIO_read1(bytesio *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t size = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&:read1",
-        _Py_convert_optional_to_ssize_t, &size)) {
+    if (!_PyArg_CheckPositional("read1", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_Py_convert_optional_to_ssize_t(args[0], &size)) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io_BytesIO_read1_impl(self, size);
 
 exit:
@@ -232,10 +244,16 @@ _io_BytesIO_readline(bytesio *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t size = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&:readline",
-        _Py_convert_optional_to_ssize_t, &size)) {
+    if (!_PyArg_CheckPositional("readline", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_Py_convert_optional_to_ssize_t(args[0], &size)) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io_BytesIO_readline_impl(self, size);
 
 exit:
@@ -298,11 +316,11 @@ _io_BytesIO_readinto(bytesio *self, PyObject *arg)
 
     if (PyObject_GetBuffer(arg, &buffer, PyBUF_WRITABLE) < 0) {
         PyErr_Clear();
-        _PyArg_BadArgument("readinto", "read-write bytes-like object", arg);
+        _PyArg_BadArgument("readinto", 0, "read-write bytes-like object", arg);
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&buffer, 'C')) {
-        _PyArg_BadArgument("readinto", "contiguous buffer", arg);
+        _PyArg_BadArgument("readinto", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = _io_BytesIO_readinto_impl(self, &buffer);
@@ -337,10 +355,16 @@ _io_BytesIO_truncate(bytesio *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t size = self->pos;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&:truncate",
-        _Py_convert_optional_to_ssize_t, &size)) {
+    if (!_PyArg_CheckPositional("truncate", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_Py_convert_optional_to_ssize_t(args[0], &size)) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io_BytesIO_truncate_impl(self, size);
 
 exit:
@@ -372,10 +396,39 @@ _io_BytesIO_seek(bytesio *self, PyObject *const *args, Py_ssize_t nargs)
     Py_ssize_t pos;
     int whence = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "n|i:seek",
-        &pos, &whence)) {
+    if (!_PyArg_CheckPositional("seek", nargs, 1, 2)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        pos = ival;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    whence = _PyLong_AsInt(args[1]);
+    if (whence == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io_BytesIO_seek_impl(self, pos, whence);
 
 exit:
@@ -450,4 +503,4 @@ _io_BytesIO___init__(PyObject *self, PyObject *args, PyObject *kwargs)
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=f6e720f38fc6e3cd input=a9049054013a1b77]*/
+/*[clinic end generated code: output=5c68eb481fa960bf input=a9049054013a1b77]*/
diff --git a/Modules/_io/clinic/fileio.c.h b/Modules/_io/clinic/fileio.c.h
index bf40f7fc4a6..280549e996d 100644
--- a/Modules/_io/clinic/fileio.c.h
+++ b/Modules/_io/clinic/fileio.c.h
@@ -158,11 +158,11 @@ _io_FileIO_readinto(fileio *self, PyObject *arg)
 
     if (PyObject_GetBuffer(arg, &buffer, PyBUF_WRITABLE) < 0) {
         PyErr_Clear();
-        _PyArg_BadArgument("readinto", "read-write bytes-like object", arg);
+        _PyArg_BadArgument("readinto", 0, "read-write bytes-like object", arg);
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&buffer, 'C')) {
-        _PyArg_BadArgument("readinto", "contiguous buffer", arg);
+        _PyArg_BadArgument("readinto", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = _io_FileIO_readinto_impl(self, &buffer);
@@ -219,10 +219,16 @@ _io_FileIO_read(fileio *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t size = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&:read",
-        _Py_convert_optional_to_ssize_t, &size)) {
+    if (!_PyArg_CheckPositional("read", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_Py_convert_optional_to_ssize_t(args[0], &size)) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io_FileIO_read_impl(self, size);
 
 exit:
@@ -255,7 +261,7 @@ _io_FileIO_write(fileio *self, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&b, 'C')) {
-        _PyArg_BadArgument("write", "contiguous buffer", arg);
+        _PyArg_BadArgument("write", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = _io_FileIO_write_impl(self, &b);
@@ -296,10 +302,23 @@ _io_FileIO_seek(fileio *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *pos;
     int whence = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "O|i:seek",
-        &pos, &whence)) {
+    if (!_PyArg_CheckPositional("seek", nargs, 1, 2)) {
         goto exit;
     }
+    pos = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    whence = _PyLong_AsInt(args[1]);
+    if (whence == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io_FileIO_seek_impl(self, pos, whence);
 
 exit:
@@ -383,4 +402,4 @@ _io_FileIO_isatty(fileio *self, PyObject *Py_UNUSED(ignored))
 #ifndef _IO_FILEIO_TRUNCATE_METHODDEF
     #define _IO_FILEIO_TRUNCATE_METHODDEF
 #endif /* !defined(_IO_FILEIO_TRUNCATE_METHODDEF) */
-/*[clinic end generated code: output=8be0ea9a5ac7aa43 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=4cf4e5f0cd656b11 input=a9049054013a1b77]*/
diff --git a/Modules/_io/clinic/iobase.c.h b/Modules/_io/clinic/iobase.c.h
index 68eaaddce22..a5c8eea3ec3 100644
--- a/Modules/_io/clinic/iobase.c.h
+++ b/Modules/_io/clinic/iobase.c.h
@@ -185,10 +185,16 @@ _io__IOBase_readline(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t limit = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&:readline",
-        _Py_convert_optional_to_ssize_t, &limit)) {
+    if (!_PyArg_CheckPositional("readline", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_Py_convert_optional_to_ssize_t(args[0], &limit)) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io__IOBase_readline_impl(self, limit);
 
 exit:
@@ -217,10 +223,16 @@ _io__IOBase_readlines(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t hint = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&:readlines",
-        _Py_convert_optional_to_ssize_t, &hint)) {
+    if (!_PyArg_CheckPositional("readlines", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_Py_convert_optional_to_ssize_t(args[0], &hint)) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io__IOBase_readlines_impl(self, hint);
 
 exit:
@@ -252,10 +264,30 @@ _io__RawIOBase_read(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t n = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|n:read",
-        &n)) {
+    if (!_PyArg_CheckPositional("read", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        n = ival;
+    }
+skip_optional:
     return_value = _io__RawIOBase_read_impl(self, n);
 
 exit:
@@ -279,4 +311,4 @@ _io__RawIOBase_readall(PyObject *self, PyObject *Py_UNUSED(ignored))
 {
     return _io__RawIOBase_readall_impl(self);
 }
-/*[clinic end generated code: output=cde4b0e96a4e69e3 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=60e43a7cbd9f314e input=a9049054013a1b77]*/
diff --git a/Modules/_io/clinic/stringio.c.h b/Modules/_io/clinic/stringio.c.h
index 3181688f109..1757d83ef7e 100644
--- a/Modules/_io/clinic/stringio.c.h
+++ b/Modules/_io/clinic/stringio.c.h
@@ -59,10 +59,16 @@ _io_StringIO_read(stringio *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t size = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&:read",
-        _Py_convert_optional_to_ssize_t, &size)) {
+    if (!_PyArg_CheckPositional("read", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_Py_convert_optional_to_ssize_t(args[0], &size)) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io_StringIO_read_impl(self, size);
 
 exit:
@@ -89,10 +95,16 @@ _io_StringIO_readline(stringio *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t size = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&:readline",
-        _Py_convert_optional_to_ssize_t, &size)) {
+    if (!_PyArg_CheckPositional("readline", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_Py_convert_optional_to_ssize_t(args[0], &size)) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io_StringIO_readline_impl(self, size);
 
 exit:
@@ -121,10 +133,16 @@ _io_StringIO_truncate(stringio *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t size = self->pos;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&:truncate",
-        _Py_convert_optional_to_ssize_t, &size)) {
+    if (!_PyArg_CheckPositional("truncate", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_Py_convert_optional_to_ssize_t(args[0], &size)) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io_StringIO_truncate_impl(self, size);
 
 exit:
@@ -156,10 +174,39 @@ _io_StringIO_seek(stringio *self, PyObject *const *args, Py_ssize_t nargs)
     Py_ssize_t pos;
     int whence = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "n|i:seek",
-        &pos, &whence)) {
+    if (!_PyArg_CheckPositional("seek", nargs, 1, 2)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        pos = ival;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    whence = _PyLong_AsInt(args[1]);
+    if (whence == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io_StringIO_seek_impl(self, pos, whence);
 
 exit:
@@ -286,4 +333,4 @@ _io_StringIO_seekable(stringio *self, PyObject *Py_UNUSED(ignored))
 {
     return _io_StringIO_seekable_impl(self);
 }
-/*[clinic end generated code: output=00c3c7a1c6ea6773 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=db5e51dcc4dae8d5 input=a9049054013a1b77]*/
diff --git a/Modules/_io/clinic/textio.c.h b/Modules/_io/clinic/textio.c.h
index f056416e33a..0ff0324f5a4 100644
--- a/Modules/_io/clinic/textio.c.h
+++ b/Modules/_io/clinic/textio.c.h
@@ -251,7 +251,7 @@ _io_TextIOWrapper_write(textio *self, PyObject *arg)
     PyObject *text;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("write", "str", arg);
+        _PyArg_BadArgument("write", 0, "str", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg) == -1) {
@@ -281,10 +281,16 @@ _io_TextIOWrapper_read(textio *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t n = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&:read",
-        _Py_convert_optional_to_ssize_t, &n)) {
+    if (!_PyArg_CheckPositional("read", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_Py_convert_optional_to_ssize_t(args[0], &n)) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io_TextIOWrapper_read_impl(self, n);
 
 exit:
@@ -308,10 +314,30 @@ _io_TextIOWrapper_readline(textio *self, PyObject *const *args, Py_ssize_t nargs
     PyObject *return_value = NULL;
     Py_ssize_t size = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|n:readline",
-        &size)) {
+    if (!_PyArg_CheckPositional("readline", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        size = ival;
+    }
+skip_optional:
     return_value = _io_TextIOWrapper_readline_impl(self, size);
 
 exit:
@@ -336,10 +362,23 @@ _io_TextIOWrapper_seek(textio *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *cookieObj;
     int whence = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "O|i:seek",
-        &cookieObj, &whence)) {
+    if (!_PyArg_CheckPositional("seek", nargs, 1, 2)) {
         goto exit;
     }
+    cookieObj = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    whence = _PyLong_AsInt(args[1]);
+    if (whence == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io_TextIOWrapper_seek_impl(self, cookieObj, whence);
 
 exit:
@@ -509,4 +548,4 @@ _io_TextIOWrapper_close(textio *self, PyObject *Py_UNUSED(ignored))
 {
     return _io_TextIOWrapper_close_impl(self);
 }
-/*[clinic end generated code: output=b933f08c2f2d85cd input=a9049054013a1b77]*/
+/*[clinic end generated code: output=8bdd1035bf878d6f input=a9049054013a1b77]*/
diff --git a/Modules/_io/clinic/winconsoleio.c.h b/Modules/_io/clinic/winconsoleio.c.h
index 65cac66c5d1..e7cd854ae25 100644
--- a/Modules/_io/clinic/winconsoleio.c.h
+++ b/Modules/_io/clinic/winconsoleio.c.h
@@ -158,11 +158,11 @@ _io__WindowsConsoleIO_readinto(winconsoleio *self, PyObject *arg)
 
     if (PyObject_GetBuffer(arg, &buffer, PyBUF_WRITABLE) < 0) {
         PyErr_Clear();
-        _PyArg_BadArgument("readinto", "read-write bytes-like object", arg);
+        _PyArg_BadArgument("readinto", 0, "read-write bytes-like object", arg);
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&buffer, 'C')) {
-        _PyArg_BadArgument("readinto", "contiguous buffer", arg);
+        _PyArg_BadArgument("readinto", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = _io__WindowsConsoleIO_readinto_impl(self, &buffer);
@@ -226,10 +226,16 @@ _io__WindowsConsoleIO_read(winconsoleio *self, PyObject *const *args, Py_ssize_t
     PyObject *return_value = NULL;
     Py_ssize_t size = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&:read",
-        _Py_convert_optional_to_ssize_t, &size)) {
+    if (!_PyArg_CheckPositional("read", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!_Py_convert_optional_to_ssize_t(args[0], &size)) {
+        goto exit;
+    }
+skip_optional:
     return_value = _io__WindowsConsoleIO_read_impl(self, size);
 
 exit:
@@ -265,7 +271,7 @@ _io__WindowsConsoleIO_write(winconsoleio *self, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&b, 'C')) {
-        _PyArg_BadArgument("write", "contiguous buffer", arg);
+        _PyArg_BadArgument("write", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = _io__WindowsConsoleIO_write_impl(self, &b);
@@ -338,4 +344,4 @@ _io__WindowsConsoleIO_isatty(winconsoleio *self, PyObject *Py_UNUSED(ignored))
 #ifndef _IO__WINDOWSCONSOLEIO_ISATTY_METHODDEF
     #define _IO__WINDOWSCONSOLEIO_ISATTY_METHODDEF
 #endif /* !defined(_IO__WINDOWSCONSOLEIO_ISATTY_METHODDEF) */
-/*[clinic end generated code: output=4337e8de65915a1e input=a9049054013a1b77]*/
+/*[clinic end generated code: output=ab0f0ee8062eecb3 input=a9049054013a1b77]*/
diff --git a/Modules/cjkcodecs/clinic/multibytecodec.c.h b/Modules/cjkcodecs/clinic/multibytecodec.c.h
index 1fef185b513..871bf339afc 100644
--- a/Modules/cjkcodecs/clinic/multibytecodec.c.h
+++ b/Modules/cjkcodecs/clinic/multibytecodec.c.h
@@ -151,7 +151,7 @@ _multibytecodec_MultibyteIncrementalEncoder_setstate(MultibyteIncrementalEncoder
     PyLongObject *statelong;
 
     if (!PyLong_Check(arg)) {
-        _PyArg_BadArgument("setstate", "int", arg);
+        _PyArg_BadArgument("setstate", 0, "int", arg);
         goto exit;
     }
     statelong = (PyLongObject *)arg;
@@ -251,7 +251,7 @@ _multibytecodec_MultibyteIncrementalDecoder_setstate(MultibyteIncrementalDecoder
     PyObject *state;
 
     if (!PyTuple_Check(arg)) {
-        _PyArg_BadArgument("setstate", "tuple", arg);
+        _PyArg_BadArgument("setstate", 0, "tuple", arg);
         goto exit;
     }
     state = arg;
@@ -422,4 +422,4 @@ PyDoc_STRVAR(_multibytecodec___create_codec__doc__,
 
 #define _MULTIBYTECODEC___CREATE_CODEC_METHODDEF    \
     {"__create_codec", (PyCFunction)_multibytecodec___create_codec, METH_O, _multibytecodec___create_codec__doc__},
-/*[clinic end generated code: output=a94364d0965adf1d input=a9049054013a1b77]*/
+/*[clinic end generated code: output=2ed7030b28a79029 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/_bz2module.c.h b/Modules/clinic/_bz2module.c.h
index dce746da413..fb643338054 100644
--- a/Modules/clinic/_bz2module.c.h
+++ b/Modules/clinic/_bz2module.c.h
@@ -29,7 +29,7 @@ _bz2_BZ2Compressor_compress(BZ2Compressor *self, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&data, 'C')) {
-        _PyArg_BadArgument("compress", "contiguous buffer", arg);
+        _PyArg_BadArgument("compress", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = _bz2_BZ2Compressor_compress_impl(self, &data);
@@ -89,10 +89,22 @@ _bz2_BZ2Compressor___init__(PyObject *self, PyObject *args, PyObject *kwargs)
         !_PyArg_NoKeywords("BZ2Compressor", kwargs)) {
         goto exit;
     }
-    if (!PyArg_ParseTuple(args, "|i:BZ2Compressor",
-        &compresslevel)) {
+    if (!_PyArg_CheckPositional("BZ2Compressor", PyTuple_GET_SIZE(args), 0, 1)) {
         goto exit;
     }
+    if (PyTuple_GET_SIZE(args) < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(PyTuple_GET_ITEM(args, 0))) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    compresslevel = _PyLong_AsInt(PyTuple_GET_ITEM(args, 0));
+    if (compresslevel == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _bz2_BZ2Compressor___init___impl((BZ2Compressor *)self, compresslevel);
 
 exit:
@@ -178,4 +190,4 @@ _bz2_BZ2Decompressor___init__(PyObject *self, PyObject *args, PyObject *kwargs)
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=8549cccdb82f57d9 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=892c6133e97ff840 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/_codecsmodule.c.h b/Modules/clinic/_codecsmodule.c.h
index 360a1341701..a8223ad0a1d 100644
--- a/Modules/clinic/_codecsmodule.c.h
+++ b/Modules/clinic/_codecsmodule.c.h
@@ -34,7 +34,7 @@ _codecs_lookup(PyObject *module, PyObject *arg)
     const char *encoding;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("lookup", "str", arg);
+        _PyArg_BadArgument("lookup", 0, "str", arg);
         goto exit;
     }
     Py_ssize_t encoding_length;
@@ -149,7 +149,7 @@ _codecs__forget_codec(PyObject *module, PyObject *arg)
     const char *encoding;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("_forget_codec", "str", arg);
+        _PyArg_BadArgument("_forget_codec", 0, "str", arg);
         goto exit;
     }
     Py_ssize_t encoding_length;
@@ -186,10 +186,48 @@ _codecs_escape_decode(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer data = {NULL, NULL};
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "s*|z:escape_decode",
-        &data, &errors)) {
+    if (!_PyArg_CheckPositional("escape_decode", nargs, 1, 2)) {
         goto exit;
     }
+    if (PyUnicode_Check(args[0])) {
+        Py_ssize_t len;
+        const char *ptr = PyUnicode_AsUTF8AndSize(args[0], &len);
+        if (ptr == NULL) {
+            goto exit;
+        }
+        PyBuffer_FillInfo(&data, args[0], (void *)ptr, len, 1, 0);
+    }
+    else { /* any bytes-like object */
+        if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+            goto exit;
+        }
+        if (!PyBuffer_IsContiguous(&data, 'C')) {
+            _PyArg_BadArgument("escape_decode", 1, "contiguous buffer", args[0]);
+            goto exit;
+        }
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("escape_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_escape_decode_impl(module, &data, errors);
 
 exit:
@@ -220,10 +258,36 @@ _codecs_escape_encode(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *data;
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "O!|z:escape_encode",
-        &PyBytes_Type, &data, &errors)) {
+    if (!_PyArg_CheckPositional("escape_encode", nargs, 1, 2)) {
         goto exit;
     }
+    if (!PyBytes_Check(args[0])) {
+        _PyArg_BadArgument("escape_encode", 1, "bytes", args[0]);
+        goto exit;
+    }
+    data = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("escape_encode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_escape_encode_impl(module, data, errors);
 
 exit:
@@ -249,10 +313,32 @@ _codecs_unicode_internal_decode(PyObject *module, PyObject *const *args, Py_ssiz
     PyObject *obj;
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "O|z:unicode_internal_decode",
-        &obj, &errors)) {
+    if (!_PyArg_CheckPositional("unicode_internal_decode", nargs, 1, 2)) {
         goto exit;
     }
+    obj = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("unicode_internal_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_unicode_internal_decode_impl(module, obj, errors);
 
 exit:
@@ -279,10 +365,50 @@ _codecs_utf_7_decode(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     const char *errors = NULL;
     int final = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*|zi:utf_7_decode",
-        &data, &errors, &final)) {
+    if (!_PyArg_CheckPositional("utf_7_decode", nargs, 1, 3)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("utf_7_decode", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("utf_7_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    final = _PyLong_AsInt(args[2]);
+    if (final == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_utf_7_decode_impl(module, &data, errors, final);
 
 exit:
@@ -314,10 +440,50 @@ _codecs_utf_8_decode(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     const char *errors = NULL;
     int final = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*|zi:utf_8_decode",
-        &data, &errors, &final)) {
+    if (!_PyArg_CheckPositional("utf_8_decode", nargs, 1, 3)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("utf_8_decode", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("utf_8_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    final = _PyLong_AsInt(args[2]);
+    if (final == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_utf_8_decode_impl(module, &data, errors, final);
 
 exit:
@@ -349,10 +515,50 @@ _codecs_utf_16_decode(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     const char *errors = NULL;
     int final = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*|zi:utf_16_decode",
-        &data, &errors, &final)) {
+    if (!_PyArg_CheckPositional("utf_16_decode", nargs, 1, 3)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("utf_16_decode", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("utf_16_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    final = _PyLong_AsInt(args[2]);
+    if (final == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_utf_16_decode_impl(module, &data, errors, final);
 
 exit:
@@ -384,10 +590,50 @@ _codecs_utf_16_le_decode(PyObject *module, PyObject *const *args, Py_ssize_t nar
     const char *errors = NULL;
     int final = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*|zi:utf_16_le_decode",
-        &data, &errors, &final)) {
+    if (!_PyArg_CheckPositional("utf_16_le_decode", nargs, 1, 3)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("utf_16_le_decode", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("utf_16_le_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    final = _PyLong_AsInt(args[2]);
+    if (final == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_utf_16_le_decode_impl(module, &data, errors, final);
 
 exit:
@@ -419,10 +665,50 @@ _codecs_utf_16_be_decode(PyObject *module, PyObject *const *args, Py_ssize_t nar
     const char *errors = NULL;
     int final = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*|zi:utf_16_be_decode",
-        &data, &errors, &final)) {
+    if (!_PyArg_CheckPositional("utf_16_be_decode", nargs, 1, 3)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("utf_16_be_decode", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("utf_16_be_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    final = _PyLong_AsInt(args[2]);
+    if (final == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_utf_16_be_decode_impl(module, &data, errors, final);
 
 exit:
@@ -456,10 +742,62 @@ _codecs_utf_16_ex_decode(PyObject *module, PyObject *const *args, Py_ssize_t nar
     int byteorder = 0;
     int final = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*|zii:utf_16_ex_decode",
-        &data, &errors, &byteorder, &final)) {
+    if (!_PyArg_CheckPositional("utf_16_ex_decode", nargs, 1, 4)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("utf_16_ex_decode", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("utf_16_ex_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    byteorder = _PyLong_AsInt(args[2]);
+    if (byteorder == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (nargs < 4) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[3])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    final = _PyLong_AsInt(args[3]);
+    if (final == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_utf_16_ex_decode_impl(module, &data, errors, byteorder, final);
 
 exit:
@@ -491,10 +829,50 @@ _codecs_utf_32_decode(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     const char *errors = NULL;
     int final = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*|zi:utf_32_decode",
-        &data, &errors, &final)) {
+    if (!_PyArg_CheckPositional("utf_32_decode", nargs, 1, 3)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("utf_32_decode", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("utf_32_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    final = _PyLong_AsInt(args[2]);
+    if (final == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_utf_32_decode_impl(module, &data, errors, final);
 
 exit:
@@ -526,10 +904,50 @@ _codecs_utf_32_le_decode(PyObject *module, PyObject *const *args, Py_ssize_t nar
     const char *errors = NULL;
     int final = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*|zi:utf_32_le_decode",
-        &data, &errors, &final)) {
+    if (!_PyArg_CheckPositional("utf_32_le_decode", nargs, 1, 3)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("utf_32_le_decode", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("utf_32_le_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    final = _PyLong_AsInt(args[2]);
+    if (final == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_utf_32_le_decode_impl(module, &data, errors, final);
 
 exit:
@@ -561,10 +979,50 @@ _codecs_utf_32_be_decode(PyObject *module, PyObject *const *args, Py_ssize_t nar
     const char *errors = NULL;
     int final = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*|zi:utf_32_be_decode",
-        &data, &errors, &final)) {
+    if (!_PyArg_CheckPositional("utf_32_be_decode", nargs, 1, 3)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("utf_32_be_decode", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("utf_32_be_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    final = _PyLong_AsInt(args[2]);
+    if (final == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_utf_32_be_decode_impl(module, &data, errors, final);
 
 exit:
@@ -598,10 +1056,62 @@ _codecs_utf_32_ex_decode(PyObject *module, PyObject *const *args, Py_ssize_t nar
     int byteorder = 0;
     int final = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*|zii:utf_32_ex_decode",
-        &data, &errors, &byteorder, &final)) {
+    if (!_PyArg_CheckPositional("utf_32_ex_decode", nargs, 1, 4)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("utf_32_ex_decode", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("utf_32_ex_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    byteorder = _PyLong_AsInt(args[2]);
+    if (byteorder == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (nargs < 4) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[3])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    final = _PyLong_AsInt(args[3]);
+    if (final == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_utf_32_ex_decode_impl(module, &data, errors, byteorder, final);
 
 exit:
@@ -632,10 +1142,48 @@ _codecs_unicode_escape_decode(PyObject *module, PyObject *const *args, Py_ssize_
     Py_buffer data = {NULL, NULL};
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "s*|z:unicode_escape_decode",
-        &data, &errors)) {
+    if (!_PyArg_CheckPositional("unicode_escape_decode", nargs, 1, 2)) {
         goto exit;
     }
+    if (PyUnicode_Check(args[0])) {
+        Py_ssize_t len;
+        const char *ptr = PyUnicode_AsUTF8AndSize(args[0], &len);
+        if (ptr == NULL) {
+            goto exit;
+        }
+        PyBuffer_FillInfo(&data, args[0], (void *)ptr, len, 1, 0);
+    }
+    else { /* any bytes-like object */
+        if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+            goto exit;
+        }
+        if (!PyBuffer_IsContiguous(&data, 'C')) {
+            _PyArg_BadArgument("unicode_escape_decode", 1, "contiguous buffer", args[0]);
+            goto exit;
+        }
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("unicode_escape_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_unicode_escape_decode_impl(module, &data, errors);
 
 exit:
@@ -666,10 +1214,48 @@ _codecs_raw_unicode_escape_decode(PyObject *module, PyObject *const *args, Py_ss
     Py_buffer data = {NULL, NULL};
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "s*|z:raw_unicode_escape_decode",
-        &data, &errors)) {
+    if (!_PyArg_CheckPositional("raw_unicode_escape_decode", nargs, 1, 2)) {
         goto exit;
     }
+    if (PyUnicode_Check(args[0])) {
+        Py_ssize_t len;
+        const char *ptr = PyUnicode_AsUTF8AndSize(args[0], &len);
+        if (ptr == NULL) {
+            goto exit;
+        }
+        PyBuffer_FillInfo(&data, args[0], (void *)ptr, len, 1, 0);
+    }
+    else { /* any bytes-like object */
+        if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+            goto exit;
+        }
+        if (!PyBuffer_IsContiguous(&data, 'C')) {
+            _PyArg_BadArgument("raw_unicode_escape_decode", 1, "contiguous buffer", args[0]);
+            goto exit;
+        }
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("raw_unicode_escape_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_raw_unicode_escape_decode_impl(module, &data, errors);
 
 exit:
@@ -700,10 +1286,38 @@ _codecs_latin_1_decode(PyObject *module, PyObject *const *args, Py_ssize_t nargs
     Py_buffer data = {NULL, NULL};
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*|z:latin_1_decode",
-        &data, &errors)) {
+    if (!_PyArg_CheckPositional("latin_1_decode", nargs, 1, 2)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("latin_1_decode", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("latin_1_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_latin_1_decode_impl(module, &data, errors);
 
 exit:
@@ -734,10 +1348,38 @@ _codecs_ascii_decode(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer data = {NULL, NULL};
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*|z:ascii_decode",
-        &data, &errors)) {
+    if (!_PyArg_CheckPositional("ascii_decode", nargs, 1, 2)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("ascii_decode", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("ascii_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_ascii_decode_impl(module, &data, errors);
 
 exit:
@@ -769,10 +1411,42 @@ _codecs_charmap_decode(PyObject *module, PyObject *const *args, Py_ssize_t nargs
     const char *errors = NULL;
     PyObject *mapping = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*|zO:charmap_decode",
-        &data, &errors, &mapping)) {
+    if (!_PyArg_CheckPositional("charmap_decode", nargs, 1, 3)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("charmap_decode", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("charmap_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    mapping = args[2];
+skip_optional:
     return_value = _codecs_charmap_decode_impl(module, &data, errors, mapping);
 
 exit:
@@ -806,10 +1480,50 @@ _codecs_mbcs_decode(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     const char *errors = NULL;
     int final = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*|zi:mbcs_decode",
-        &data, &errors, &final)) {
+    if (!_PyArg_CheckPositional("mbcs_decode", nargs, 1, 3)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("mbcs_decode", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("mbcs_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    final = _PyLong_AsInt(args[2]);
+    if (final == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_mbcs_decode_impl(module, &data, errors, final);
 
 exit:
@@ -845,10 +1559,50 @@ _codecs_oem_decode(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     const char *errors = NULL;
     int final = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*|zi:oem_decode",
-        &data, &errors, &final)) {
+    if (!_PyArg_CheckPositional("oem_decode", nargs, 1, 3)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("oem_decode", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("oem_decode", 2, "str or None", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    final = _PyLong_AsInt(args[2]);
+    if (final == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_oem_decode_impl(module, &data, errors, final);
 
 exit:
@@ -885,10 +1639,59 @@ _codecs_code_page_decode(PyObject *module, PyObject *const *args, Py_ssize_t nar
     const char *errors = NULL;
     int final = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "iy*|zi:code_page_decode",
-        &codepage, &data, &errors, &final)) {
+    if (!_PyArg_CheckPositional("code_page_decode", nargs, 2, 4)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    codepage = _PyLong_AsInt(args[0]);
+    if (codepage == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[1], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("code_page_decode", 2, "contiguous buffer", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (args[2] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[2])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[2], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("code_page_decode", 3, "str or None", args[2]);
+        goto exit;
+    }
+    if (nargs < 4) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[3])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    final = _PyLong_AsInt(args[3]);
+    if (final == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_code_page_decode_impl(module, codepage, &data, errors, final);
 
 exit:
@@ -921,10 +1724,48 @@ _codecs_readbuffer_encode(PyObject *module, PyObject *const *args, Py_ssize_t na
     Py_buffer data = {NULL, NULL};
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "s*|z:readbuffer_encode",
-        &data, &errors)) {
+    if (!_PyArg_CheckPositional("readbuffer_encode", nargs, 1, 2)) {
         goto exit;
     }
+    if (PyUnicode_Check(args[0])) {
+        Py_ssize_t len;
+        const char *ptr = PyUnicode_AsUTF8AndSize(args[0], &len);
+        if (ptr == NULL) {
+            goto exit;
+        }
+        PyBuffer_FillInfo(&data, args[0], (void *)ptr, len, 1, 0);
+    }
+    else { /* any bytes-like object */
+        if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+            goto exit;
+        }
+        if (!PyBuffer_IsContiguous(&data, 'C')) {
+            _PyArg_BadArgument("readbuffer_encode", 1, "contiguous buffer", args[0]);
+            goto exit;
+        }
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("readbuffer_encode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_readbuffer_encode_impl(module, &data, errors);
 
 exit:
@@ -955,10 +1796,32 @@ _codecs_unicode_internal_encode(PyObject *module, PyObject *const *args, Py_ssiz
     PyObject *obj;
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "O|z:unicode_internal_encode",
-        &obj, &errors)) {
+    if (!_PyArg_CheckPositional("unicode_internal_encode", nargs, 1, 2)) {
         goto exit;
     }
+    obj = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("unicode_internal_encode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_unicode_internal_encode_impl(module, obj, errors);
 
 exit:
@@ -984,10 +1847,39 @@ _codecs_utf_7_encode(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *str;
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "U|z:utf_7_encode",
-        &str, &errors)) {
+    if (!_PyArg_CheckPositional("utf_7_encode", nargs, 1, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("utf_7_encode", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    str = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("utf_7_encode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_utf_7_encode_impl(module, str, errors);
 
 exit:
@@ -1013,10 +1905,39 @@ _codecs_utf_8_encode(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *str;
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "U|z:utf_8_encode",
-        &str, &errors)) {
+    if (!_PyArg_CheckPositional("utf_8_encode", nargs, 1, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("utf_8_encode", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    str = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("utf_8_encode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_utf_8_encode_impl(module, str, errors);
 
 exit:
@@ -1043,10 +1964,51 @@ _codecs_utf_16_encode(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     const char *errors = NULL;
     int byteorder = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "U|zi:utf_16_encode",
-        &str, &errors, &byteorder)) {
+    if (!_PyArg_CheckPositional("utf_16_encode", nargs, 1, 3)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("utf_16_encode", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    str = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("utf_16_encode", 2, "str or None", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    byteorder = _PyLong_AsInt(args[2]);
+    if (byteorder == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_utf_16_encode_impl(module, str, errors, byteorder);
 
 exit:
@@ -1072,10 +2034,39 @@ _codecs_utf_16_le_encode(PyObject *module, PyObject *const *args, Py_ssize_t nar
     PyObject *str;
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "U|z:utf_16_le_encode",
-        &str, &errors)) {
+    if (!_PyArg_CheckPositional("utf_16_le_encode", nargs, 1, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("utf_16_le_encode", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    str = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("utf_16_le_encode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_utf_16_le_encode_impl(module, str, errors);
 
 exit:
@@ -1101,10 +2092,39 @@ _codecs_utf_16_be_encode(PyObject *module, PyObject *const *args, Py_ssize_t nar
     PyObject *str;
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "U|z:utf_16_be_encode",
-        &str, &errors)) {
+    if (!_PyArg_CheckPositional("utf_16_be_encode", nargs, 1, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("utf_16_be_encode", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    str = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("utf_16_be_encode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_utf_16_be_encode_impl(module, str, errors);
 
 exit:
@@ -1131,10 +2151,51 @@ _codecs_utf_32_encode(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     const char *errors = NULL;
     int byteorder = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "U|zi:utf_32_encode",
-        &str, &errors, &byteorder)) {
+    if (!_PyArg_CheckPositional("utf_32_encode", nargs, 1, 3)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("utf_32_encode", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    str = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("utf_32_encode", 2, "str or None", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    byteorder = _PyLong_AsInt(args[2]);
+    if (byteorder == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_utf_32_encode_impl(module, str, errors, byteorder);
 
 exit:
@@ -1160,10 +2221,39 @@ _codecs_utf_32_le_encode(PyObject *module, PyObject *const *args, Py_ssize_t nar
     PyObject *str;
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "U|z:utf_32_le_encode",
-        &str, &errors)) {
+    if (!_PyArg_CheckPositional("utf_32_le_encode", nargs, 1, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("utf_32_le_encode", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    str = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("utf_32_le_encode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_utf_32_le_encode_impl(module, str, errors);
 
 exit:
@@ -1189,10 +2279,39 @@ _codecs_utf_32_be_encode(PyObject *module, PyObject *const *args, Py_ssize_t nar
     PyObject *str;
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "U|z:utf_32_be_encode",
-        &str, &errors)) {
+    if (!_PyArg_CheckPositional("utf_32_be_encode", nargs, 1, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("utf_32_be_encode", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    str = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("utf_32_be_encode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_utf_32_be_encode_impl(module, str, errors);
 
 exit:
@@ -1218,10 +2337,39 @@ _codecs_unicode_escape_encode(PyObject *module, PyObject *const *args, Py_ssize_
     PyObject *str;
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "U|z:unicode_escape_encode",
-        &str, &errors)) {
+    if (!_PyArg_CheckPositional("unicode_escape_encode", nargs, 1, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("unicode_escape_encode", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    str = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("unicode_escape_encode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_unicode_escape_encode_impl(module, str, errors);
 
 exit:
@@ -1247,10 +2395,39 @@ _codecs_raw_unicode_escape_encode(PyObject *module, PyObject *const *args, Py_ss
     PyObject *str;
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "U|z:raw_unicode_escape_encode",
-        &str, &errors)) {
+    if (!_PyArg_CheckPositional("raw_unicode_escape_encode", nargs, 1, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("raw_unicode_escape_encode", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    str = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("raw_unicode_escape_encode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_raw_unicode_escape_encode_impl(module, str, errors);
 
 exit:
@@ -1276,10 +2453,39 @@ _codecs_latin_1_encode(PyObject *module, PyObject *const *args, Py_ssize_t nargs
     PyObject *str;
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "U|z:latin_1_encode",
-        &str, &errors)) {
+    if (!_PyArg_CheckPositional("latin_1_encode", nargs, 1, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("latin_1_encode", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    str = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("latin_1_encode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_latin_1_encode_impl(module, str, errors);
 
 exit:
@@ -1305,10 +2511,39 @@ _codecs_ascii_encode(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *str;
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "U|z:ascii_encode",
-        &str, &errors)) {
+    if (!_PyArg_CheckPositional("ascii_encode", nargs, 1, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("ascii_encode", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    str = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("ascii_encode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_ascii_encode_impl(module, str, errors);
 
 exit:
@@ -1335,10 +2570,43 @@ _codecs_charmap_encode(PyObject *module, PyObject *const *args, Py_ssize_t nargs
     const char *errors = NULL;
     PyObject *mapping = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "U|zO:charmap_encode",
-        &str, &errors, &mapping)) {
+    if (!_PyArg_CheckPositional("charmap_encode", nargs, 1, 3)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("charmap_encode", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    str = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("charmap_encode", 2, "str or None", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    mapping = args[2];
+skip_optional:
     return_value = _codecs_charmap_encode_impl(module, str, errors, mapping);
 
 exit:
@@ -1363,7 +2631,7 @@ _codecs_charmap_build(PyObject *module, PyObject *arg)
     PyObject *map;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("charmap_build", "str", arg);
+        _PyArg_BadArgument("charmap_build", 0, "str", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg) == -1) {
@@ -1396,10 +2664,39 @@ _codecs_mbcs_encode(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *str;
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "U|z:mbcs_encode",
-        &str, &errors)) {
+    if (!_PyArg_CheckPositional("mbcs_encode", nargs, 1, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("mbcs_encode", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    str = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("mbcs_encode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_mbcs_encode_impl(module, str, errors);
 
 exit:
@@ -1428,10 +2725,39 @@ _codecs_oem_encode(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *str;
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "U|z:oem_encode",
-        &str, &errors)) {
+    if (!_PyArg_CheckPositional("oem_encode", nargs, 1, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("oem_encode", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    str = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (args[1] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[1])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[1], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("oem_encode", 2, "str or None", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_oem_encode_impl(module, str, errors);
 
 exit:
@@ -1462,10 +2788,48 @@ _codecs_code_page_encode(PyObject *module, PyObject *const *args, Py_ssize_t nar
     PyObject *str;
     const char *errors = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "iU|z:code_page_encode",
-        &code_page, &str, &errors)) {
+    if (!_PyArg_CheckPositional("code_page_encode", nargs, 2, 3)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    code_page = _PyLong_AsInt(args[0]);
+    if (code_page == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (!PyUnicode_Check(args[1])) {
+        _PyArg_BadArgument("code_page_encode", 2, "str", args[1]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[1]) == -1) {
+        goto exit;
+    }
+    str = args[1];
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (args[2] == Py_None) {
+        errors = NULL;
+    }
+    else if (PyUnicode_Check(args[2])) {
+        Py_ssize_t errors_length;
+        errors = PyUnicode_AsUTF8AndSize(args[2], &errors_length);
+        if (errors == NULL) {
+            goto exit;
+        }
+        if (strlen(errors) != (size_t)errors_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("code_page_encode", 3, "str or None", args[2]);
+        goto exit;
+    }
+skip_optional:
     return_value = _codecs_code_page_encode_impl(module, code_page, str, errors);
 
 exit:
@@ -1498,10 +2862,23 @@ _codecs_register_error(PyObject *module, PyObject *const *args, Py_ssize_t nargs
     const char *errors;
     PyObject *handler;
 
-    if (!_PyArg_ParseStack(args, nargs, "sO:register_error",
-        &errors, &handler)) {
+    if (!_PyArg_CheckPositional("register_error", nargs, 2, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("register_error", 1, "str", args[0]);
+        goto exit;
+    }
+    Py_ssize_t errors_length;
+    errors = PyUnicode_AsUTF8AndSize(args[0], &errors_length);
+    if (errors == NULL) {
+        goto exit;
+    }
+    if (strlen(errors) != (size_t)errors_length) {
+        PyErr_SetString(PyExc_ValueError, "embedded null character");
+        goto exit;
+    }
+    handler = args[1];
     return_value = _codecs_register_error_impl(module, errors, handler);
 
 exit:
@@ -1530,7 +2907,7 @@ _codecs_lookup_error(PyObject *module, PyObject *arg)
     const char *name;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("lookup_error", "str", arg);
+        _PyArg_BadArgument("lookup_error", 0, "str", arg);
         goto exit;
     }
     Py_ssize_t name_length;
@@ -1571,4 +2948,4 @@ exit:
 #ifndef _CODECS_CODE_PAGE_ENCODE_METHODDEF
     #define _CODECS_CODE_PAGE_ENCODE_METHODDEF
 #endif /* !defined(_CODECS_CODE_PAGE_ENCODE_METHODDEF) */
-/*[clinic end generated code: output=c2d2b917b78a4c45 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=85ea29db163ee74c input=a9049054013a1b77]*/
diff --git a/Modules/clinic/_collectionsmodule.c.h b/Modules/clinic/_collectionsmodule.c.h
index 12626c1f661..ed3b1b50f9b 100644
--- a/Modules/clinic/_collectionsmodule.c.h
+++ b/Modules/clinic/_collectionsmodule.c.h
@@ -16,13 +16,30 @@ tuplegetter_new(PyTypeObject *type, PyObject *args, PyObject *kwargs)
         !_PyArg_NoKeywords("_tuplegetter", kwargs)) {
         goto exit;
     }
-    if (!PyArg_ParseTuple(args, "nO:_tuplegetter",
-        &index, &doc)) {
+    if (!_PyArg_CheckPositional("_tuplegetter", PyTuple_GET_SIZE(args), 2, 2)) {
         goto exit;
     }
+    if (PyFloat_Check(PyTuple_GET_ITEM(args, 0))) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(PyTuple_GET_ITEM(args, 0));
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        index = ival;
+    }
+    doc = PyTuple_GET_ITEM(args, 1);
     return_value = tuplegetter_new_impl(type, index, doc);
 
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=83746071eacc28d3 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=51bd572577ca7111 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/_cryptmodule.c.h b/Modules/clinic/_cryptmodule.c.h
index baa31e2d2fb..2fcb0c1bf12 100644
--- a/Modules/clinic/_cryptmodule.c.h
+++ b/Modules/clinic/_cryptmodule.c.h
@@ -26,8 +26,33 @@ crypt_crypt(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     const char *word;
     const char *salt;
 
-    if (!_PyArg_ParseStack(args, nargs, "ss:crypt",
-        &word, &salt)) {
+    if (!_PyArg_CheckPositional("crypt", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("crypt", 1, "str", args[0]);
+        goto exit;
+    }
+    Py_ssize_t word_length;
+    word = PyUnicode_AsUTF8AndSize(args[0], &word_length);
+    if (word == NULL) {
+        goto exit;
+    }
+    if (strlen(word) != (size_t)word_length) {
+        PyErr_SetString(PyExc_ValueError, "embedded null character");
+        goto exit;
+    }
+    if (!PyUnicode_Check(args[1])) {
+        _PyArg_BadArgument("crypt", 2, "str", args[1]);
+        goto exit;
+    }
+    Py_ssize_t salt_length;
+    salt = PyUnicode_AsUTF8AndSize(args[1], &salt_length);
+    if (salt == NULL) {
+        goto exit;
+    }
+    if (strlen(salt) != (size_t)salt_length) {
+        PyErr_SetString(PyExc_ValueError, "embedded null character");
         goto exit;
     }
     return_value = crypt_crypt_impl(module, word, salt);
@@ -35,4 +60,4 @@ crypt_crypt(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=79001dbfdd623ff9 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=3f75d4d4be4dddbb input=a9049054013a1b77]*/
diff --git a/Modules/clinic/_curses_panel.c.h b/Modules/clinic/_curses_panel.c.h
index 2e569c546bd..ed59c3ba398 100644
--- a/Modules/clinic/_curses_panel.c.h
+++ b/Modules/clinic/_curses_panel.c.h
@@ -149,8 +149,25 @@ _curses_panel_panel_move(PyCursesPanelObject *self, PyObject *const *args, Py_ss
     int y;
     int x;
 
-    if (!_PyArg_ParseStack(args, nargs, "ii:move",
-        &y, &x)) {
+    if (!_PyArg_CheckPositional("move", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    y = _PyLong_AsInt(args[0]);
+    if (y == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    x = _PyLong_AsInt(args[1]);
+    if (x == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = _curses_panel_panel_move_impl(self, y, x);
@@ -197,7 +214,7 @@ _curses_panel_panel_replace(PyCursesPanelObject *self, PyObject *arg)
     PyCursesWindowObject *win;
 
     if (!PyObject_TypeCheck(arg, &PyCursesWindow_Type)) {
-        _PyArg_BadArgument("replace", (&PyCursesWindow_Type)->tp_name, arg);
+        _PyArg_BadArgument("replace", 0, (&PyCursesWindow_Type)->tp_name, arg);
         goto exit;
     }
     win = (PyCursesWindowObject *)arg;
@@ -271,7 +288,7 @@ _curses_panel_new_panel(PyObject *module, PyObject *arg)
     PyCursesWindowObject *win;
 
     if (!PyObject_TypeCheck(arg, &PyCursesWindow_Type)) {
-        _PyArg_BadArgument("new_panel", (&PyCursesWindow_Type)->tp_name, arg);
+        _PyArg_BadArgument("new_panel", 0, (&PyCursesWindow_Type)->tp_name, arg);
         goto exit;
     }
     win = (PyCursesWindowObject *)arg;
@@ -318,4 +335,4 @@ _curses_panel_update_panels(PyObject *module, PyObject *Py_UNUSED(ignored))
 {
     return _curses_panel_update_panels_impl(module);
 }
-/*[clinic end generated code: output=4b211b4015e29100 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=ac1f56e6c3d4cc57 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/_cursesmodule.c.h b/Modules/clinic/_cursesmodule.c.h
index 01c70976c42..0988581363e 100644
--- a/Modules/clinic/_cursesmodule.c.h
+++ b/Modules/clinic/_cursesmodule.c.h
@@ -245,10 +245,23 @@ _curses_window_bkgd(PyCursesWindowObject *self, PyObject *const *args, Py_ssize_
     PyObject *ch;
     long attr = A_NORMAL;
 
-    if (!_PyArg_ParseStack(args, nargs, "O|l:bkgd",
-        &ch, &attr)) {
+    if (!_PyArg_CheckPositional("bkgd", nargs, 1, 2)) {
         goto exit;
     }
+    ch = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    attr = PyLong_AsLong(args[1]);
+    if (attr == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _curses_window_bkgd_impl(self, ch, attr);
 
 exit:
@@ -379,10 +392,23 @@ _curses_window_bkgdset(PyCursesWindowObject *self, PyObject *const *args, Py_ssi
     PyObject *ch;
     long attr = A_NORMAL;
 
-    if (!_PyArg_ParseStack(args, nargs, "O|l:bkgdset",
-        &ch, &attr)) {
+    if (!_PyArg_CheckPositional("bkgdset", nargs, 1, 2)) {
         goto exit;
     }
+    ch = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    attr = PyLong_AsLong(args[1]);
+    if (attr == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _curses_window_bkgdset_impl(self, ch, attr);
 
 exit:
@@ -623,10 +649,23 @@ _curses_window_echochar(PyCursesWindowObject *self, PyObject *const *args, Py_ss
     PyObject *ch;
     long attr = A_NORMAL;
 
-    if (!_PyArg_ParseStack(args, nargs, "O|l:echochar",
-        &ch, &attr)) {
+    if (!_PyArg_CheckPositional("echochar", nargs, 1, 2)) {
         goto exit;
     }
+    ch = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    attr = PyLong_AsLong(args[1]);
+    if (attr == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _curses_window_echochar_impl(self, ch, attr);
 
 exit:
@@ -660,8 +699,25 @@ _curses_window_enclose(PyCursesWindowObject *self, PyObject *const *args, Py_ssi
     int x;
     long _return_value;
 
-    if (!_PyArg_ParseStack(args, nargs, "ii:enclose",
-        &y, &x)) {
+    if (!_PyArg_CheckPositional("enclose", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    y = _PyLong_AsInt(args[0]);
+    if (y == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    x = _PyLong_AsInt(args[1]);
+    if (x == -1 && PyErr_Occurred()) {
         goto exit;
     }
     _return_value = _curses_window_enclose_impl(self, y, x);
@@ -1462,8 +1518,25 @@ _curses_window_redrawln(PyCursesWindowObject *self, PyObject *const *args, Py_ss
     int beg;
     int num;
 
-    if (!_PyArg_ParseStack(args, nargs, "ii:redrawln",
-        &beg, &num)) {
+    if (!_PyArg_CheckPositional("redrawln", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    beg = _PyLong_AsInt(args[0]);
+    if (beg == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    num = _PyLong_AsInt(args[1]);
+    if (num == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = _curses_window_redrawln_impl(self, beg, num);
@@ -1554,8 +1627,25 @@ _curses_window_setscrreg(PyCursesWindowObject *self, PyObject *const *args, Py_s
     int top;
     int bottom;
 
-    if (!_PyArg_ParseStack(args, nargs, "ii:setscrreg",
-        &top, &bottom)) {
+    if (!_PyArg_CheckPositional("setscrreg", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    top = _PyLong_AsInt(args[0]);
+    if (top == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    bottom = _PyLong_AsInt(args[1]);
+    if (bottom == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = _curses_window_setscrreg_impl(self, top, bottom);
@@ -1878,10 +1968,22 @@ _curses_cbreak(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     int flag = 1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|i:cbreak",
-        &flag)) {
+    if (!_PyArg_CheckPositional("cbreak", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    flag = _PyLong_AsInt(args[0]);
+    if (flag == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _curses_cbreak_impl(module, flag);
 
 exit:
@@ -2158,10 +2260,22 @@ _curses_echo(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     int flag = 1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|i:echo",
-        &flag)) {
+    if (!_PyArg_CheckPositional("echo", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    flag = _PyLong_AsInt(args[0]);
+    if (flag == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _curses_echo_impl(module, flag);
 
 exit:
@@ -2321,10 +2435,65 @@ _curses_ungetmouse(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int z;
     unsigned long bstate;
 
-    if (!_PyArg_ParseStack(args, nargs, "hiiik:ungetmouse",
-        &id, &x, &y, &z, &bstate)) {
+    if (!_PyArg_CheckPositional("ungetmouse", nargs, 5, 5)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        long ival = PyLong_AsLong(args[0]);
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        else if (ival < SHRT_MIN) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "signed short integer is less than minimum");
+            goto exit;
+        }
+        else if (ival > SHRT_MAX) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "signed short integer is greater than maximum");
+            goto exit;
+        }
+        else {
+            id = (short) ival;
+        }
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    x = _PyLong_AsInt(args[1]);
+    if (x == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    y = _PyLong_AsInt(args[2]);
+    if (y == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[3])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    z = _PyLong_AsInt(args[3]);
+    if (z == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (!PyLong_Check(args[4])) {
+        _PyArg_BadArgument("ungetmouse", 5, "int", args[4]);
+        goto exit;
+    }
+    bstate = PyLong_AsUnsignedLongMask(args[4]);
     return_value = _curses_ungetmouse_impl(module, id, x, y, z, bstate);
 
 exit:
@@ -2527,10 +2696,105 @@ _curses_init_color(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     short g;
     short b;
 
-    if (!_PyArg_ParseStack(args, nargs, "hhhh:init_color",
-        &color_number, &r, &g, &b)) {
+    if (!_PyArg_CheckPositional("init_color", nargs, 4, 4)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        long ival = PyLong_AsLong(args[0]);
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        else if (ival < SHRT_MIN) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "signed short integer is less than minimum");
+            goto exit;
+        }
+        else if (ival > SHRT_MAX) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "signed short integer is greater than maximum");
+            goto exit;
+        }
+        else {
+            color_number = (short) ival;
+        }
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        long ival = PyLong_AsLong(args[1]);
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        else if (ival < SHRT_MIN) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "signed short integer is less than minimum");
+            goto exit;
+        }
+        else if (ival > SHRT_MAX) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "signed short integer is greater than maximum");
+            goto exit;
+        }
+        else {
+            r = (short) ival;
+        }
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        long ival = PyLong_AsLong(args[2]);
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        else if (ival < SHRT_MIN) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "signed short integer is less than minimum");
+            goto exit;
+        }
+        else if (ival > SHRT_MAX) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "signed short integer is greater than maximum");
+            goto exit;
+        }
+        else {
+            g = (short) ival;
+        }
+    }
+    if (PyFloat_Check(args[3])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        long ival = PyLong_AsLong(args[3]);
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        else if (ival < SHRT_MIN) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "signed short integer is less than minimum");
+            goto exit;
+        }
+        else if (ival > SHRT_MAX) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "signed short integer is greater than maximum");
+            goto exit;
+        }
+        else {
+            b = (short) ival;
+        }
+    }
     return_value = _curses_init_color_impl(module, color_number, r, g, b);
 
 exit:
@@ -2568,10 +2832,81 @@ _curses_init_pair(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     short fg;
     short bg;
 
-    if (!_PyArg_ParseStack(args, nargs, "hhh:init_pair",
-        &pair_number, &fg, &bg)) {
+    if (!_PyArg_CheckPositional("init_pair", nargs, 3, 3)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        long ival = PyLong_AsLong(args[0]);
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        else if (ival < SHRT_MIN) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "signed short integer is less than minimum");
+            goto exit;
+        }
+        else if (ival > SHRT_MAX) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "signed short integer is greater than maximum");
+            goto exit;
+        }
+        else {
+            pair_number = (short) ival;
+        }
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        long ival = PyLong_AsLong(args[1]);
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        else if (ival < SHRT_MIN) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "signed short integer is less than minimum");
+            goto exit;
+        }
+        else if (ival > SHRT_MAX) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "signed short integer is greater than maximum");
+            goto exit;
+        }
+        else {
+            fg = (short) ival;
+        }
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        long ival = PyLong_AsLong(args[2]);
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        else if (ival < SHRT_MIN) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "signed short integer is less than minimum");
+            goto exit;
+        }
+        else if (ival > SHRT_MAX) {
+            PyErr_SetString(PyExc_OverflowError,
+                            "signed short integer is greater than maximum");
+            goto exit;
+        }
+        else {
+            bg = (short) ival;
+        }
+    }
     return_value = _curses_init_pair_impl(module, pair_number, fg, bg);
 
 exit:
@@ -2712,8 +3047,25 @@ _curses_is_term_resized(PyObject *module, PyObject *const *args, Py_ssize_t narg
     int nlines;
     int ncols;
 
-    if (!_PyArg_ParseStack(args, nargs, "ii:is_term_resized",
-        &nlines, &ncols)) {
+    if (!_PyArg_CheckPositional("is_term_resized", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    nlines = _PyLong_AsInt(args[0]);
+    if (nlines == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    ncols = _PyLong_AsInt(args[1]);
+    if (ncols == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = _curses_is_term_resized_impl(module, nlines, ncols);
@@ -2905,7 +3257,7 @@ _curses_mousemask(PyObject *module, PyObject *arg)
     unsigned long newmask;
 
     if (!PyLong_Check(arg)) {
-        _PyArg_BadArgument("mousemask", "int", arg);
+        _PyArg_BadArgument("mousemask", 0, "int", arg);
         goto exit;
     }
     newmask = PyLong_AsUnsignedLongMask(arg);
@@ -2977,8 +3329,25 @@ _curses_newpad(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int nlines;
     int ncols;
 
-    if (!_PyArg_ParseStack(args, nargs, "ii:newpad",
-        &nlines, &ncols)) {
+    if (!_PyArg_CheckPositional("newpad", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    nlines = _PyLong_AsInt(args[0]);
+    if (nlines == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    ncols = _PyLong_AsInt(args[1]);
+    if (ncols == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = _curses_newpad_impl(module, nlines, ncols);
@@ -3066,10 +3435,22 @@ _curses_nl(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     int flag = 1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|i:nl",
-        &flag)) {
+    if (!_PyArg_CheckPositional("nl", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    flag = _PyLong_AsInt(args[0]);
+    if (flag == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _curses_nl_impl(module, flag);
 
 exit:
@@ -3317,10 +3698,22 @@ _curses_qiflush(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     int flag = 1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|i:qiflush",
-        &flag)) {
+    if (!_PyArg_CheckPositional("qiflush", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    flag = _PyLong_AsInt(args[0]);
+    if (flag == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _curses_qiflush_impl(module, flag);
 
 exit:
@@ -3383,10 +3776,22 @@ _curses_raw(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     int flag = 1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|i:raw",
-        &flag)) {
+    if (!_PyArg_CheckPositional("raw", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    flag = _PyLong_AsInt(args[0]);
+    if (flag == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _curses_raw_impl(module, flag);
 
 exit:
@@ -3476,8 +3881,25 @@ _curses_resizeterm(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int nlines;
     int ncols;
 
-    if (!_PyArg_ParseStack(args, nargs, "ii:resizeterm",
-        &nlines, &ncols)) {
+    if (!_PyArg_CheckPositional("resizeterm", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    nlines = _PyLong_AsInt(args[0]);
+    if (nlines == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    ncols = _PyLong_AsInt(args[1]);
+    if (ncols == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = _curses_resizeterm_impl(module, nlines, ncols);
@@ -3520,8 +3942,25 @@ _curses_resize_term(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int nlines;
     int ncols;
 
-    if (!_PyArg_ParseStack(args, nargs, "ii:resize_term",
-        &nlines, &ncols)) {
+    if (!_PyArg_CheckPositional("resize_term", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    nlines = _PyLong_AsInt(args[0]);
+    if (nlines == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    ncols = _PyLong_AsInt(args[1]);
+    if (ncols == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = _curses_resize_term_impl(module, nlines, ncols);
@@ -3578,8 +4017,25 @@ _curses_setsyx(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int y;
     int x;
 
-    if (!_PyArg_ParseStack(args, nargs, "ii:setsyx",
-        &y, &x)) {
+    if (!_PyArg_CheckPositional("setsyx", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    y = _PyLong_AsInt(args[0]);
+    if (y == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    x = _PyLong_AsInt(args[1]);
+    if (x == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = _curses_setsyx_impl(module, y, x);
@@ -3676,7 +4132,7 @@ _curses_tigetflag(PyObject *module, PyObject *arg)
     const char *capname;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("tigetflag", "str", arg);
+        _PyArg_BadArgument("tigetflag", 0, "str", arg);
         goto exit;
     }
     Py_ssize_t capname_length;
@@ -3719,7 +4175,7 @@ _curses_tigetnum(PyObject *module, PyObject *arg)
     const char *capname;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("tigetnum", "str", arg);
+        _PyArg_BadArgument("tigetnum", 0, "str", arg);
         goto exit;
     }
     Py_ssize_t capname_length;
@@ -3762,7 +4218,7 @@ _curses_tigetstr(PyObject *module, PyObject *arg)
     const char *capname;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("tigetstr", "str", arg);
+        _PyArg_BadArgument("tigetstr", 0, "str", arg);
         goto exit;
     }
     Py_ssize_t capname_length;
@@ -4044,4 +4500,4 @@ _curses_use_default_colors(PyObject *module, PyObject *Py_UNUSED(ignored))
 #ifndef _CURSES_USE_DEFAULT_COLORS_METHODDEF
     #define _CURSES_USE_DEFAULT_COLORS_METHODDEF
 #endif /* !defined(_CURSES_USE_DEFAULT_COLORS_METHODDEF) */
-/*[clinic end generated code: output=a2bbced3c5d29d64 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=ceb2e32ee1370033 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/_dbmmodule.c.h b/Modules/clinic/_dbmmodule.c.h
index c0908623c97..e54c69cf708 100644
--- a/Modules/clinic/_dbmmodule.c.h
+++ b/Modules/clinic/_dbmmodule.c.h
@@ -132,13 +132,49 @@ dbmopen(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     const char *flags = "r";
     int mode = 438;
 
-    if (!_PyArg_ParseStack(args, nargs, "U|si:open",
-        &filename, &flags, &mode)) {
+    if (!_PyArg_CheckPositional("open", nargs, 1, 3)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("open", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    filename = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!PyUnicode_Check(args[1])) {
+        _PyArg_BadArgument("open", 2, "str", args[1]);
+        goto exit;
+    }
+    Py_ssize_t flags_length;
+    flags = PyUnicode_AsUTF8AndSize(args[1], &flags_length);
+    if (flags == NULL) {
+        goto exit;
+    }
+    if (strlen(flags) != (size_t)flags_length) {
+        PyErr_SetString(PyExc_ValueError, "embedded null character");
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    mode = _PyLong_AsInt(args[2]);
+    if (mode == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = dbmopen_impl(module, filename, flags, mode);
 
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=e4585e78f5821b5b input=a9049054013a1b77]*/
+/*[clinic end generated code: output=7f5d30ef5d820b8a input=a9049054013a1b77]*/
diff --git a/Modules/clinic/_elementtree.c.h b/Modules/clinic/_elementtree.c.h
index e5107eb24fe..89689839640 100644
--- a/Modules/clinic/_elementtree.c.h
+++ b/Modules/clinic/_elementtree.c.h
@@ -20,7 +20,7 @@ _elementtree_Element_append(ElementObject *self, PyObject *arg)
     PyObject *subelement;
 
     if (!PyObject_TypeCheck(arg, &Element_Type)) {
-        _PyArg_BadArgument("append", (&Element_Type)->tp_name, arg);
+        _PyArg_BadArgument("append", 0, (&Element_Type)->tp_name, arg);
         goto exit;
     }
     subelement = arg;
@@ -82,7 +82,7 @@ _elementtree_Element___deepcopy__(ElementObject *self, PyObject *arg)
     PyObject *memo;
 
     if (!PyDict_Check(arg)) {
-        _PyArg_BadArgument("__deepcopy__", "dict", arg);
+        _PyArg_BadArgument("__deepcopy__", 0, "dict", arg);
         goto exit;
     }
     memo = arg;
@@ -420,10 +420,31 @@ _elementtree_Element_insert(ElementObject *self, PyObject *const *args, Py_ssize
     Py_ssize_t index;
     PyObject *subelement;
 
-    if (!_PyArg_ParseStack(args, nargs, "nO!:insert",
-        &index, &Element_Type, &subelement)) {
+    if (!_PyArg_CheckPositional("insert", nargs, 2, 2)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        index = ival;
+    }
+    if (!PyObject_TypeCheck(args[1], &Element_Type)) {
+        _PyArg_BadArgument("insert", 2, (&Element_Type)->tp_name, args[1]);
+        goto exit;
+    }
+    subelement = args[1];
     return_value = _elementtree_Element_insert_impl(self, index, subelement);
 
 exit:
@@ -512,7 +533,7 @@ _elementtree_Element_remove(ElementObject *self, PyObject *arg)
     PyObject *subelement;
 
     if (!PyObject_TypeCheck(arg, &Element_Type)) {
-        _PyArg_BadArgument("remove", (&Element_Type)->tp_name, arg);
+        _PyArg_BadArgument("remove", 0, (&Element_Type)->tp_name, arg);
         goto exit;
     }
     subelement = arg;
@@ -723,4 +744,4 @@ _elementtree_XMLParser__setevents(XMLParserObject *self, PyObject *const *args,
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=398640585689c5ed input=a9049054013a1b77]*/
+/*[clinic end generated code: output=6bbedd24b709dc00 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/_gdbmmodule.c.h b/Modules/clinic/_gdbmmodule.c.h
index 5edc440b181..9475264ef9d 100644
--- a/Modules/clinic/_gdbmmodule.c.h
+++ b/Modules/clinic/_gdbmmodule.c.h
@@ -245,13 +245,49 @@ dbmopen(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     const char *flags = "r";
     int mode = 438;
 
-    if (!_PyArg_ParseStack(args, nargs, "U|si:open",
-        &filename, &flags, &mode)) {
+    if (!_PyArg_CheckPositional("open", nargs, 1, 3)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("open", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    filename = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!PyUnicode_Check(args[1])) {
+        _PyArg_BadArgument("open", 2, "str", args[1]);
+        goto exit;
+    }
+    Py_ssize_t flags_length;
+    flags = PyUnicode_AsUTF8AndSize(args[1], &flags_length);
+    if (flags == NULL) {
+        goto exit;
+    }
+    if (strlen(flags) != (size_t)flags_length) {
+        PyErr_SetString(PyExc_ValueError, "embedded null character");
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    mode = _PyLong_AsInt(args[2]);
+    if (mode == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = dbmopen_impl(module, filename, flags, mode);
 
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=5ca4361417bf96cb input=a9049054013a1b77]*/
+/*[clinic end generated code: output=05f06065d2dc1f9e input=a9049054013a1b77]*/
diff --git a/Modules/clinic/_lzmamodule.c.h b/Modules/clinic/_lzmamodule.c.h
index 46d2988ad3e..aeb98a66039 100644
--- a/Modules/clinic/_lzmamodule.c.h
+++ b/Modules/clinic/_lzmamodule.c.h
@@ -29,7 +29,7 @@ _lzma_LZMACompressor_compress(Compressor *self, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&data, 'C')) {
-        _PyArg_BadArgument("compress", "contiguous buffer", arg);
+        _PyArg_BadArgument("compress", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = _lzma_LZMACompressor_compress_impl(self, &data);
@@ -252,8 +252,17 @@ _lzma__decode_filter_properties(PyObject *module, PyObject *const *args, Py_ssiz
     lzma_vli filter_id;
     Py_buffer encoded_props = {NULL, NULL};
 
-    if (!_PyArg_ParseStack(args, nargs, "O&y*:_decode_filter_properties",
-        lzma_vli_converter, &filter_id, &encoded_props)) {
+    if (!_PyArg_CheckPositional("_decode_filter_properties", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (!lzma_vli_converter(args[0], &filter_id)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[1], &encoded_props, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&encoded_props, 'C')) {
+        _PyArg_BadArgument("_decode_filter_properties", 2, "contiguous buffer", args[1]);
         goto exit;
     }
     return_value = _lzma__decode_filter_properties_impl(module, filter_id, &encoded_props);
@@ -266,4 +275,4 @@ exit:
 
     return return_value;
 }
-/*[clinic end generated code: output=df061bfc2067a90a input=a9049054013a1b77]*/
+/*[clinic end generated code: output=47e4732df79509ad input=a9049054013a1b77]*/
diff --git a/Modules/clinic/_operator.c.h b/Modules/clinic/_operator.c.h
index 9d7b20c1cc0..72c0e57ea2b 100644
--- a/Modules/clinic/_operator.c.h
+++ b/Modules/clinic/_operator.c.h
@@ -1416,10 +1416,31 @@ _operator_length_hint(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_ssize_t default_value = 0;
     Py_ssize_t _return_value;
 
-    if (!_PyArg_ParseStack(args, nargs, "O|n:length_hint",
-        &obj, &default_value)) {
+    if (!_PyArg_CheckPositional("length_hint", nargs, 1, 2)) {
         goto exit;
     }
+    obj = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[1]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        default_value = ival;
+    }
+skip_optional:
     _return_value = _operator_length_hint_impl(module, obj, default_value);
     if ((_return_value == -1) && PyErr_Occurred()) {
         goto exit;
@@ -1469,4 +1490,4 @@ _operator__compare_digest(PyObject *module, PyObject *const *args, Py_ssize_t na
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=424b884884ab20b7 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=b382bece80a5a254 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/_ssl.c.h b/Modules/clinic/_ssl.c.h
index e149077edee..3ec30c3c985 100644
--- a/Modules/clinic/_ssl.c.h
+++ b/Modules/clinic/_ssl.c.h
@@ -71,10 +71,17 @@ _ssl__SSLSocket_getpeercert(PySSLSocket *self, PyObject *const *args, Py_ssize_t
     PyObject *return_value = NULL;
     int binary_mode = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "|p:getpeercert",
-        &binary_mode)) {
+    if (!_PyArg_CheckPositional("getpeercert", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    binary_mode = PyObject_IsTrue(args[0]);
+    if (binary_mode < 0) {
+        goto exit;
+    }
+skip_optional:
     return_value = _ssl__SSLSocket_getpeercert_impl(self, binary_mode);
 
 exit:
@@ -215,7 +222,7 @@ _ssl__SSLSocket_write(PySSLSocket *self, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&b, 'C')) {
-        _PyArg_BadArgument("write", "contiguous buffer", arg);
+        _PyArg_BadArgument("write", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = _ssl__SSLSocket_write_impl(self, &b);
@@ -377,8 +384,16 @@ _ssl__SSLContext(PyTypeObject *type, PyObject *args, PyObject *kwargs)
         !_PyArg_NoKeywords("_SSLContext", kwargs)) {
         goto exit;
     }
-    if (!PyArg_ParseTuple(args, "i:_SSLContext",
-        &proto_version)) {
+    if (!_PyArg_CheckPositional("_SSLContext", PyTuple_GET_SIZE(args), 1, 1)) {
+        goto exit;
+    }
+    if (PyFloat_Check(PyTuple_GET_ITEM(args, 0))) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    proto_version = _PyLong_AsInt(PyTuple_GET_ITEM(args, 0));
+    if (proto_version == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = _ssl__SSLContext_impl(type, proto_version);
@@ -405,7 +420,7 @@ _ssl__SSLContext_set_ciphers(PySSLContext *self, PyObject *arg)
     const char *cipherlist;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("set_ciphers", "str", arg);
+        _PyArg_BadArgument("set_ciphers", 0, "str", arg);
         goto exit;
     }
     Py_ssize_t cipherlist_length;
@@ -466,7 +481,7 @@ _ssl__SSLContext__set_npn_protocols(PySSLContext *self, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&protos, 'C')) {
-        _PyArg_BadArgument("_set_npn_protocols", "contiguous buffer", arg);
+        _PyArg_BadArgument("_set_npn_protocols", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = _ssl__SSLContext__set_npn_protocols_impl(self, &protos);
@@ -502,7 +517,7 @@ _ssl__SSLContext__set_alpn_protocols(PySSLContext *self, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&protos, 'C')) {
-        _PyArg_BadArgument("_set_alpn_protocols", "contiguous buffer", arg);
+        _PyArg_BadArgument("_set_alpn_protocols", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = _ssl__SSLContext__set_alpn_protocols_impl(self, &protos);
@@ -815,10 +830,22 @@ _ssl_MemoryBIO_read(PySSLMemoryBIO *self, PyObject *const *args, Py_ssize_t narg
     PyObject *return_value = NULL;
     int len = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|i:read",
-        &len)) {
+    if (!_PyArg_CheckPositional("read", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    len = _PyLong_AsInt(args[0]);
+    if (len == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _ssl_MemoryBIO_read_impl(self, len);
 
 exit:
@@ -849,7 +876,7 @@ _ssl_MemoryBIO_write(PySSLMemoryBIO *self, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&b, 'C')) {
-        _PyArg_BadArgument("write", "contiguous buffer", arg);
+        _PyArg_BadArgument("write", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = _ssl_MemoryBIO_write_impl(self, &b);
@@ -905,8 +932,28 @@ _ssl_RAND_add(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer view = {NULL, NULL};
     double entropy;
 
-    if (!_PyArg_ParseStack(args, nargs, "s*d:RAND_add",
-        &view, &entropy)) {
+    if (!_PyArg_CheckPositional("RAND_add", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyUnicode_Check(args[0])) {
+        Py_ssize_t len;
+        const char *ptr = PyUnicode_AsUTF8AndSize(args[0], &len);
+        if (ptr == NULL) {
+            goto exit;
+        }
+        PyBuffer_FillInfo(&view, args[0], (void *)ptr, len, 1, 0);
+    }
+    else { /* any bytes-like object */
+        if (PyObject_GetBuffer(args[0], &view, PyBUF_SIMPLE) != 0) {
+            goto exit;
+        }
+        if (!PyBuffer_IsContiguous(&view, 'C')) {
+            _PyArg_BadArgument("RAND_add", 1, "contiguous buffer", args[0]);
+            goto exit;
+        }
+    }
+    entropy = PyFloat_AsDouble(args[1]);
+    if (PyErr_Occurred()) {
         goto exit;
     }
     return_value = _ssl_RAND_add_impl(module, &view, entropy);
@@ -1237,4 +1284,4 @@ exit:
 #ifndef _SSL_ENUM_CRLS_METHODDEF
     #define _SSL_ENUM_CRLS_METHODDEF
 #endif /* !defined(_SSL_ENUM_CRLS_METHODDEF) */
-/*[clinic end generated code: output=c2dca2ef4cbef4e2 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=ac3fb15ca27500f2 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/_struct.c.h b/Modules/clinic/_struct.c.h
index 3a186e4c98f..2cc2d216f8b 100644
--- a/Modules/clinic/_struct.c.h
+++ b/Modules/clinic/_struct.c.h
@@ -61,7 +61,7 @@ Struct_unpack(PyStructObject *self, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&buffer, 'C')) {
-        _PyArg_BadArgument("unpack", "contiguous buffer", arg);
+        _PyArg_BadArgument("unpack", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = Struct_unpack_impl(self, &buffer);
@@ -209,8 +209,17 @@ unpack(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyStructObject *s_object = NULL;
     Py_buffer buffer = {NULL, NULL};
 
-    if (!_PyArg_ParseStack(args, nargs, "O&y*:unpack",
-        cache_struct_converter, &s_object, &buffer)) {
+    if (!_PyArg_CheckPositional("unpack", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (!cache_struct_converter(args[0], &s_object)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[1], &buffer, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&buffer, 'C')) {
+        _PyArg_BadArgument("unpack", 2, "contiguous buffer", args[1]);
         goto exit;
     }
     return_value = unpack_impl(module, s_object, &buffer);
@@ -295,10 +304,13 @@ iter_unpack(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyStructObject *s_object = NULL;
     PyObject *buffer;
 
-    if (!_PyArg_ParseStack(args, nargs, "O&O:iter_unpack",
-        cache_struct_converter, &s_object, &buffer)) {
+    if (!_PyArg_CheckPositional("iter_unpack", nargs, 2, 2)) {
         goto exit;
     }
+    if (!cache_struct_converter(args[0], &s_object)) {
+        goto exit;
+    }
+    buffer = args[1];
     return_value = iter_unpack_impl(module, s_object, buffer);
 
 exit:
@@ -307,4 +319,4 @@ exit:
 
     return return_value;
 }
-/*[clinic end generated code: output=01516bea2641fe01 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=ac595db9d2b271aa input=a9049054013a1b77]*/
diff --git a/Modules/clinic/_tkinter.c.h b/Modules/clinic/_tkinter.c.h
index 1eedd2bd3bc..0a3e7ff5fc9 100644
--- a/Modules/clinic/_tkinter.c.h
+++ b/Modules/clinic/_tkinter.c.h
@@ -20,7 +20,7 @@ _tkinter_tkapp_eval(TkappObject *self, PyObject *arg)
     const char *script;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("eval", "str", arg);
+        _PyArg_BadArgument("eval", 0, "str", arg);
         goto exit;
     }
     Py_ssize_t script_length;
@@ -56,7 +56,7 @@ _tkinter_tkapp_evalfile(TkappObject *self, PyObject *arg)
     const char *fileName;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("evalfile", "str", arg);
+        _PyArg_BadArgument("evalfile", 0, "str", arg);
         goto exit;
     }
     Py_ssize_t fileName_length;
@@ -92,7 +92,7 @@ _tkinter_tkapp_record(TkappObject *self, PyObject *arg)
     const char *script;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("record", "str", arg);
+        _PyArg_BadArgument("record", 0, "str", arg);
         goto exit;
     }
     Py_ssize_t script_length;
@@ -128,7 +128,7 @@ _tkinter_tkapp_adderrorinfo(TkappObject *self, PyObject *arg)
     const char *msg;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("adderrorinfo", "str", arg);
+        _PyArg_BadArgument("adderrorinfo", 0, "str", arg);
         goto exit;
     }
     Py_ssize_t msg_length;
@@ -188,7 +188,7 @@ _tkinter_tkapp_exprstring(TkappObject *self, PyObject *arg)
     const char *s;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("exprstring", "str", arg);
+        _PyArg_BadArgument("exprstring", 0, "str", arg);
         goto exit;
     }
     Py_ssize_t s_length;
@@ -224,7 +224,7 @@ _tkinter_tkapp_exprlong(TkappObject *self, PyObject *arg)
     const char *s;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("exprlong", "str", arg);
+        _PyArg_BadArgument("exprlong", 0, "str", arg);
         goto exit;
     }
     Py_ssize_t s_length;
@@ -260,7 +260,7 @@ _tkinter_tkapp_exprdouble(TkappObject *self, PyObject *arg)
     const char *s;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("exprdouble", "str", arg);
+        _PyArg_BadArgument("exprdouble", 0, "str", arg);
         goto exit;
     }
     Py_ssize_t s_length;
@@ -296,7 +296,7 @@ _tkinter_tkapp_exprboolean(TkappObject *self, PyObject *arg)
     const char *s;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("exprboolean", "str", arg);
+        _PyArg_BadArgument("exprboolean", 0, "str", arg);
         goto exit;
     }
     Py_ssize_t s_length;
@@ -349,10 +349,23 @@ _tkinter_tkapp_createcommand(TkappObject *self, PyObject *const *args, Py_ssize_
     const char *name;
     PyObject *func;
 
-    if (!_PyArg_ParseStack(args, nargs, "sO:createcommand",
-        &name, &func)) {
+    if (!_PyArg_CheckPositional("createcommand", nargs, 2, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("createcommand", 1, "str", args[0]);
+        goto exit;
+    }
+    Py_ssize_t name_length;
+    name = PyUnicode_AsUTF8AndSize(args[0], &name_length);
+    if (name == NULL) {
+        goto exit;
+    }
+    if (strlen(name) != (size_t)name_length) {
+        PyErr_SetString(PyExc_ValueError, "embedded null character");
+        goto exit;
+    }
+    func = args[1];
     return_value = _tkinter_tkapp_createcommand_impl(self, name, func);
 
 exit:
@@ -377,7 +390,7 @@ _tkinter_tkapp_deletecommand(TkappObject *self, PyObject *arg)
     const char *name;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("deletecommand", "str", arg);
+        _PyArg_BadArgument("deletecommand", 0, "str", arg);
         goto exit;
     }
     Py_ssize_t name_length;
@@ -417,10 +430,20 @@ _tkinter_tkapp_createfilehandler(TkappObject *self, PyObject *const *args, Py_ss
     int mask;
     PyObject *func;
 
-    if (!_PyArg_ParseStack(args, nargs, "OiO:createfilehandler",
-        &file, &mask, &func)) {
+    if (!_PyArg_CheckPositional("createfilehandler", nargs, 3, 3)) {
         goto exit;
     }
+    file = args[0];
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    mask = _PyLong_AsInt(args[1]);
+    if (mask == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    func = args[2];
     return_value = _tkinter_tkapp_createfilehandler_impl(self, file, mask, func);
 
 exit:
@@ -477,10 +500,19 @@ _tkinter_tkapp_createtimerhandler(TkappObject *self, PyObject *const *args, Py_s
     int milliseconds;
     PyObject *func;
 
-    if (!_PyArg_ParseStack(args, nargs, "iO:createtimerhandler",
-        &milliseconds, &func)) {
+    if (!_PyArg_CheckPositional("createtimerhandler", nargs, 2, 2)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    milliseconds = _PyLong_AsInt(args[0]);
+    if (milliseconds == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    func = args[1];
     return_value = _tkinter_tkapp_createtimerhandler_impl(self, milliseconds, func);
 
 exit:
@@ -504,10 +536,22 @@ _tkinter_tkapp_mainloop(TkappObject *self, PyObject *const *args, Py_ssize_t nar
     PyObject *return_value = NULL;
     int threshold = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "|i:mainloop",
-        &threshold)) {
+    if (!_PyArg_CheckPositional("mainloop", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    threshold = _PyLong_AsInt(args[0]);
+    if (threshold == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _tkinter_tkapp_mainloop_impl(self, threshold);
 
 exit:
@@ -531,10 +575,22 @@ _tkinter_tkapp_dooneevent(TkappObject *self, PyObject *const *args, Py_ssize_t n
     PyObject *return_value = NULL;
     int flags = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "|i:dooneevent",
-        &flags)) {
+    if (!_PyArg_CheckPositional("dooneevent", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    flags = _PyLong_AsInt(args[0]);
+    if (flags == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _tkinter_tkapp_dooneevent_impl(self, flags);
 
 exit:
@@ -654,10 +710,132 @@ _tkinter_create(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int sync = 0;
     const char *use = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "|zssiiiiz:create",
-        &screenName, &baseName, &className, &interactive, &wantobjects, &wantTk, &sync, &use)) {
+    if (!_PyArg_CheckPositional("create", nargs, 0, 8)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (args[0] == Py_None) {
+        screenName = NULL;
+    }
+    else if (PyUnicode_Check(args[0])) {
+        Py_ssize_t screenName_length;
+        screenName = PyUnicode_AsUTF8AndSize(args[0], &screenName_length);
+        if (screenName == NULL) {
+            goto exit;
+        }
+        if (strlen(screenName) != (size_t)screenName_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("create", 1, "str or None", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!PyUnicode_Check(args[1])) {
+        _PyArg_BadArgument("create", 2, "str", args[1]);
+        goto exit;
+    }
+    Py_ssize_t baseName_length;
+    baseName = PyUnicode_AsUTF8AndSize(args[1], &baseName_length);
+    if (baseName == NULL) {
+        goto exit;
+    }
+    if (strlen(baseName) != (size_t)baseName_length) {
+        PyErr_SetString(PyExc_ValueError, "embedded null character");
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (!PyUnicode_Check(args[2])) {
+        _PyArg_BadArgument("create", 3, "str", args[2]);
+        goto exit;
+    }
+    Py_ssize_t className_length;
+    className = PyUnicode_AsUTF8AndSize(args[2], &className_length);
+    if (className == NULL) {
+        goto exit;
+    }
+    if (strlen(className) != (size_t)className_length) {
+        PyErr_SetString(PyExc_ValueError, "embedded null character");
+        goto exit;
+    }
+    if (nargs < 4) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[3])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    interactive = _PyLong_AsInt(args[3]);
+    if (interactive == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (nargs < 5) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[4])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    wantobjects = _PyLong_AsInt(args[4]);
+    if (wantobjects == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (nargs < 6) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[5])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    wantTk = _PyLong_AsInt(args[5]);
+    if (wantTk == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (nargs < 7) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[6])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    sync = _PyLong_AsInt(args[6]);
+    if (sync == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (nargs < 8) {
+        goto skip_optional;
+    }
+    if (args[7] == Py_None) {
+        use = NULL;
+    }
+    else if (PyUnicode_Check(args[7])) {
+        Py_ssize_t use_length;
+        use = PyUnicode_AsUTF8AndSize(args[7], &use_length);
+        if (use == NULL) {
+            goto exit;
+        }
+        if (strlen(use) != (size_t)use_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("create", 8, "str or None", args[7]);
+        goto exit;
+    }
+skip_optional:
     return_value = _tkinter_create_impl(module, screenName, baseName, className, interactive, wantobjects, wantTk, sync, use);
 
 exit:
@@ -734,4 +912,4 @@ exit:
 #ifndef _TKINTER_TKAPP_DELETEFILEHANDLER_METHODDEF
     #define _TKINTER_TKAPP_DELETEFILEHANDLER_METHODDEF
 #endif /* !defined(_TKINTER_TKAPP_DELETEFILEHANDLER_METHODDEF) */
-/*[clinic end generated code: output=d84b0e794824c511 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=2cf95f0101f3dbca input=a9049054013a1b77]*/
diff --git a/Modules/clinic/_tracemalloc.c.h b/Modules/clinic/_tracemalloc.c.h
index aa736ec2fd0..68fafdc3833 100644
--- a/Modules/clinic/_tracemalloc.c.h
+++ b/Modules/clinic/_tracemalloc.c.h
@@ -95,10 +95,22 @@ _tracemalloc_start(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     int nframe = 1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|i:start",
-        &nframe)) {
+    if (!_PyArg_CheckPositional("start", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    nframe = _PyLong_AsInt(args[0]);
+    if (nframe == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = _tracemalloc_start_impl(module, nframe);
 
 exit:
@@ -185,4 +197,4 @@ _tracemalloc_get_traced_memory(PyObject *module, PyObject *Py_UNUSED(ignored))
 {
     return _tracemalloc_get_traced_memory_impl(module);
 }
-/*[clinic end generated code: output=d4a2dd3eaba9f72d input=a9049054013a1b77]*/
+/*[clinic end generated code: output=1bc96dc569706afa input=a9049054013a1b77]*/
diff --git a/Modules/clinic/_weakref.c.h b/Modules/clinic/_weakref.c.h
index 21f00ffd205..aa0d77f7180 100644
--- a/Modules/clinic/_weakref.c.h
+++ b/Modules/clinic/_weakref.c.h
@@ -50,13 +50,18 @@ _weakref__remove_dead_weakref(PyObject *module, PyObject *const *args, Py_ssize_
     PyObject *dct;
     PyObject *key;
 
-    if (!_PyArg_ParseStack(args, nargs, "O!O:_remove_dead_weakref",
-        &PyDict_Type, &dct, &key)) {
+    if (!_PyArg_CheckPositional("_remove_dead_weakref", nargs, 2, 2)) {
         goto exit;
     }
+    if (!PyDict_Check(args[0])) {
+        _PyArg_BadArgument("_remove_dead_weakref", 1, "dict", args[0]);
+        goto exit;
+    }
+    dct = args[0];
+    key = args[1];
     return_value = _weakref__remove_dead_weakref_impl(module, dct, key);
 
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=927e889feb8a7dc4 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=eae22e2d2e43120e input=a9049054013a1b77]*/
diff --git a/Modules/clinic/arraymodule.c.h b/Modules/clinic/arraymodule.c.h
index eb081ad0718..5f45b7cf673 100644
--- a/Modules/clinic/arraymodule.c.h
+++ b/Modules/clinic/arraymodule.c.h
@@ -76,10 +76,30 @@ array_array_pop(arrayobject *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t i = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|n:pop",
-        &i)) {
+    if (!_PyArg_CheckPositional("pop", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        i = ival;
+    }
+skip_optional:
     return_value = array_array_pop_impl(self, i);
 
 exit:
@@ -114,10 +134,27 @@ array_array_insert(arrayobject *self, PyObject *const *args, Py_ssize_t nargs)
     Py_ssize_t i;
     PyObject *v;
 
-    if (!_PyArg_ParseStack(args, nargs, "nO:insert",
-        &i, &v)) {
+    if (!_PyArg_CheckPositional("insert", nargs, 2, 2)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        i = ival;
+    }
+    v = args[1];
     return_value = array_array_insert_impl(self, i, v);
 
 exit:
@@ -212,10 +249,27 @@ array_array_fromfile(arrayobject *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *f;
     Py_ssize_t n;
 
-    if (!_PyArg_ParseStack(args, nargs, "On:fromfile",
-        &f, &n)) {
+    if (!_PyArg_CheckPositional("fromfile", nargs, 2, 2)) {
         goto exit;
     }
+    f = args[0];
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[1]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        n = ival;
+    }
     return_value = array_array_fromfile_impl(self, f, n);
 
 exit:
@@ -291,7 +345,7 @@ array_array_fromstring(arrayobject *self, PyObject *arg)
             goto exit;
         }
         if (!PyBuffer_IsContiguous(&buffer, 'C')) {
-            _PyArg_BadArgument("fromstring", "contiguous buffer", arg);
+            _PyArg_BadArgument("fromstring", 0, "contiguous buffer", arg);
             goto exit;
         }
     }
@@ -328,7 +382,7 @@ array_array_frombytes(arrayobject *self, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&buffer, 'C')) {
-        _PyArg_BadArgument("frombytes", "contiguous buffer", arg);
+        _PyArg_BadArgument("frombytes", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = array_array_frombytes_impl(self, &buffer);
@@ -478,10 +532,32 @@ array__array_reconstructor(PyObject *module, PyObject *const *args, Py_ssize_t n
     enum machine_format_code mformat_code;
     PyObject *items;
 
-    if (!_PyArg_ParseStack(args, nargs, "OCiO:_array_reconstructor",
-        &arraytype, &typecode, &mformat_code, &items)) {
+    if (!_PyArg_CheckPositional("_array_reconstructor", nargs, 4, 4)) {
         goto exit;
     }
+    arraytype = (PyTypeObject *)args[0];
+    if (!PyUnicode_Check(args[1])) {
+        _PyArg_BadArgument("_array_reconstructor", 2, "a unicode character", args[1]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[1])) {
+        goto exit;
+    }
+    if (PyUnicode_GET_LENGTH(args[1]) != 1) {
+        _PyArg_BadArgument("_array_reconstructor", 2, "a unicode character", args[1]);
+        goto exit;
+    }
+    typecode = PyUnicode_READ_CHAR(args[1], 0);
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    mformat_code = _PyLong_AsInt(args[2]);
+    if (mformat_code == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    items = args[3];
     return_value = array__array_reconstructor_impl(module, arraytype, typecode, mformat_code, items);
 
 exit:
@@ -523,4 +599,4 @@ PyDoc_STRVAR(array_arrayiterator___setstate____doc__,
 
 #define ARRAY_ARRAYITERATOR___SETSTATE___METHODDEF    \
     {"__setstate__", (PyCFunction)array_arrayiterator___setstate__, METH_O, array_arrayiterator___setstate____doc__},
-/*[clinic end generated code: output=15da19d2ece09d22 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=c9a40f11f1a866fb input=a9049054013a1b77]*/
diff --git a/Modules/clinic/audioop.c.h b/Modules/clinic/audioop.c.h
index 1eae9aaf5d8..4ea7155373b 100644
--- a/Modules/clinic/audioop.c.h
+++ b/Modules/clinic/audioop.c.h
@@ -23,10 +23,42 @@ audioop_getsample(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int width;
     Py_ssize_t index;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*in:getsample",
-        &fragment, &width, &index)) {
+    if (!_PyArg_CheckPositional("getsample", nargs, 3, 3)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("getsample", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[2]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        index = ival;
+    }
     return_value = audioop_getsample_impl(module, &fragment, width, index);
 
 exit:
@@ -57,8 +89,23 @@ audioop_max(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer fragment = {NULL, NULL};
     int width;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*i:max",
-        &fragment, &width)) {
+    if (!_PyArg_CheckPositional("max", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("max", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_max_impl(module, &fragment, width);
@@ -91,8 +138,23 @@ audioop_minmax(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer fragment = {NULL, NULL};
     int width;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*i:minmax",
-        &fragment, &width)) {
+    if (!_PyArg_CheckPositional("minmax", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("minmax", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_minmax_impl(module, &fragment, width);
@@ -125,8 +187,23 @@ audioop_avg(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer fragment = {NULL, NULL};
     int width;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*i:avg",
-        &fragment, &width)) {
+    if (!_PyArg_CheckPositional("avg", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("avg", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_avg_impl(module, &fragment, width);
@@ -159,8 +236,23 @@ audioop_rms(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer fragment = {NULL, NULL};
     int width;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*i:rms",
-        &fragment, &width)) {
+    if (!_PyArg_CheckPositional("rms", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("rms", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_rms_impl(module, &fragment, width);
@@ -194,8 +286,21 @@ audioop_findfit(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer fragment = {NULL, NULL};
     Py_buffer reference = {NULL, NULL};
 
-    if (!_PyArg_ParseStack(args, nargs, "y*y*:findfit",
-        &fragment, &reference)) {
+    if (!_PyArg_CheckPositional("findfit", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("findfit", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[1], &reference, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&reference, 'C')) {
+        _PyArg_BadArgument("findfit", 2, "contiguous buffer", args[1]);
         goto exit;
     }
     return_value = audioop_findfit_impl(module, &fragment, &reference);
@@ -233,8 +338,21 @@ audioop_findfactor(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer fragment = {NULL, NULL};
     Py_buffer reference = {NULL, NULL};
 
-    if (!_PyArg_ParseStack(args, nargs, "y*y*:findfactor",
-        &fragment, &reference)) {
+    if (!_PyArg_CheckPositional("findfactor", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("findfactor", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[1], &reference, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&reference, 'C')) {
+        _PyArg_BadArgument("findfactor", 2, "contiguous buffer", args[1]);
         goto exit;
     }
     return_value = audioop_findfactor_impl(module, &fragment, &reference);
@@ -272,10 +390,33 @@ audioop_findmax(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer fragment = {NULL, NULL};
     Py_ssize_t length;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*n:findmax",
-        &fragment, &length)) {
+    if (!_PyArg_CheckPositional("findmax", nargs, 2, 2)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("findmax", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[1]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        length = ival;
+    }
     return_value = audioop_findmax_impl(module, &fragment, length);
 
 exit:
@@ -306,8 +447,23 @@ audioop_avgpp(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer fragment = {NULL, NULL};
     int width;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*i:avgpp",
-        &fragment, &width)) {
+    if (!_PyArg_CheckPositional("avgpp", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("avgpp", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_avgpp_impl(module, &fragment, width);
@@ -340,8 +496,23 @@ audioop_maxpp(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer fragment = {NULL, NULL};
     int width;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*i:maxpp",
-        &fragment, &width)) {
+    if (!_PyArg_CheckPositional("maxpp", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("maxpp", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_maxpp_impl(module, &fragment, width);
@@ -374,8 +545,23 @@ audioop_cross(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer fragment = {NULL, NULL};
     int width;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*i:cross",
-        &fragment, &width)) {
+    if (!_PyArg_CheckPositional("cross", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("cross", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_cross_impl(module, &fragment, width);
@@ -410,8 +596,27 @@ audioop_mul(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int width;
     double factor;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*id:mul",
-        &fragment, &width, &factor)) {
+    if (!_PyArg_CheckPositional("mul", nargs, 3, 3)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("mul", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    factor = PyFloat_AsDouble(args[2]);
+    if (PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_mul_impl(module, &fragment, width, factor);
@@ -447,8 +652,31 @@ audioop_tomono(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     double lfactor;
     double rfactor;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*idd:tomono",
-        &fragment, &width, &lfactor, &rfactor)) {
+    if (!_PyArg_CheckPositional("tomono", nargs, 4, 4)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("tomono", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    lfactor = PyFloat_AsDouble(args[2]);
+    if (PyErr_Occurred()) {
+        goto exit;
+    }
+    rfactor = PyFloat_AsDouble(args[3]);
+    if (PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_tomono_impl(module, &fragment, width, lfactor, rfactor);
@@ -484,8 +712,31 @@ audioop_tostereo(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     double lfactor;
     double rfactor;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*idd:tostereo",
-        &fragment, &width, &lfactor, &rfactor)) {
+    if (!_PyArg_CheckPositional("tostereo", nargs, 4, 4)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("tostereo", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    lfactor = PyFloat_AsDouble(args[2]);
+    if (PyErr_Occurred()) {
+        goto exit;
+    }
+    rfactor = PyFloat_AsDouble(args[3]);
+    if (PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_tostereo_impl(module, &fragment, width, lfactor, rfactor);
@@ -520,8 +771,30 @@ audioop_add(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer fragment2 = {NULL, NULL};
     int width;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*y*i:add",
-        &fragment1, &fragment2, &width)) {
+    if (!_PyArg_CheckPositional("add", nargs, 3, 3)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment1, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment1, 'C')) {
+        _PyArg_BadArgument("add", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[1], &fragment2, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment2, 'C')) {
+        _PyArg_BadArgument("add", 2, "contiguous buffer", args[1]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[2]);
+    if (width == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_add_impl(module, &fragment1, &fragment2, width);
@@ -559,8 +832,32 @@ audioop_bias(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int width;
     int bias;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*ii:bias",
-        &fragment, &width, &bias)) {
+    if (!_PyArg_CheckPositional("bias", nargs, 3, 3)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("bias", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    bias = _PyLong_AsInt(args[2]);
+    if (bias == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_bias_impl(module, &fragment, width, bias);
@@ -593,8 +890,23 @@ audioop_reverse(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer fragment = {NULL, NULL};
     int width;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*i:reverse",
-        &fragment, &width)) {
+    if (!_PyArg_CheckPositional("reverse", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("reverse", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_reverse_impl(module, &fragment, width);
@@ -627,8 +939,23 @@ audioop_byteswap(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer fragment = {NULL, NULL};
     int width;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*i:byteswap",
-        &fragment, &width)) {
+    if (!_PyArg_CheckPositional("byteswap", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("byteswap", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_byteswap_impl(module, &fragment, width);
@@ -663,8 +990,32 @@ audioop_lin2lin(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int width;
     int newwidth;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*ii:lin2lin",
-        &fragment, &width, &newwidth)) {
+    if (!_PyArg_CheckPositional("lin2lin", nargs, 3, 3)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("lin2lin", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    newwidth = _PyLong_AsInt(args[2]);
+    if (newwidth == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_lin2lin_impl(module, &fragment, width, newwidth);
@@ -706,10 +1057,78 @@ audioop_ratecv(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int weightA = 1;
     int weightB = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*iiiiO|ii:ratecv",
-        &fragment, &width, &nchannels, &inrate, &outrate, &state, &weightA, &weightB)) {
+    if (!_PyArg_CheckPositional("ratecv", nargs, 6, 8)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("ratecv", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    nchannels = _PyLong_AsInt(args[2]);
+    if (nchannels == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[3])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    inrate = _PyLong_AsInt(args[3]);
+    if (inrate == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[4])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    outrate = _PyLong_AsInt(args[4]);
+    if (outrate == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    state = args[5];
+    if (nargs < 7) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[6])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    weightA = _PyLong_AsInt(args[6]);
+    if (weightA == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (nargs < 8) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[7])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    weightB = _PyLong_AsInt(args[7]);
+    if (weightB == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = audioop_ratecv_impl(module, &fragment, width, nchannels, inrate, outrate, state, weightA, weightB);
 
 exit:
@@ -740,8 +1159,23 @@ audioop_lin2ulaw(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer fragment = {NULL, NULL};
     int width;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*i:lin2ulaw",
-        &fragment, &width)) {
+    if (!_PyArg_CheckPositional("lin2ulaw", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("lin2ulaw", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_lin2ulaw_impl(module, &fragment, width);
@@ -774,8 +1208,23 @@ audioop_ulaw2lin(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer fragment = {NULL, NULL};
     int width;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*i:ulaw2lin",
-        &fragment, &width)) {
+    if (!_PyArg_CheckPositional("ulaw2lin", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("ulaw2lin", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_ulaw2lin_impl(module, &fragment, width);
@@ -808,8 +1257,23 @@ audioop_lin2alaw(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer fragment = {NULL, NULL};
     int width;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*i:lin2alaw",
-        &fragment, &width)) {
+    if (!_PyArg_CheckPositional("lin2alaw", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("lin2alaw", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_lin2alaw_impl(module, &fragment, width);
@@ -842,8 +1306,23 @@ audioop_alaw2lin(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer fragment = {NULL, NULL};
     int width;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*i:alaw2lin",
-        &fragment, &width)) {
+    if (!_PyArg_CheckPositional("alaw2lin", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("alaw2lin", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = audioop_alaw2lin_impl(module, &fragment, width);
@@ -878,10 +1357,26 @@ audioop_lin2adpcm(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int width;
     PyObject *state;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*iO:lin2adpcm",
-        &fragment, &width, &state)) {
+    if (!_PyArg_CheckPositional("lin2adpcm", nargs, 3, 3)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("lin2adpcm", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    state = args[2];
     return_value = audioop_lin2adpcm_impl(module, &fragment, width, state);
 
 exit:
@@ -914,10 +1409,26 @@ audioop_adpcm2lin(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int width;
     PyObject *state;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*iO:adpcm2lin",
-        &fragment, &width, &state)) {
+    if (!_PyArg_CheckPositional("adpcm2lin", nargs, 3, 3)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &fragment, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&fragment, 'C')) {
+        _PyArg_BadArgument("adpcm2lin", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    width = _PyLong_AsInt(args[1]);
+    if (width == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    state = args[2];
     return_value = audioop_adpcm2lin_impl(module, &fragment, width, state);
 
 exit:
@@ -928,4 +1439,4 @@ exit:
 
     return return_value;
 }
-/*[clinic end generated code: output=d197b1559196a48a input=a9049054013a1b77]*/
+/*[clinic end generated code: output=2b173a25726252e9 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/binascii.c.h b/Modules/clinic/binascii.c.h
index 91f261cb300..3295833e87a 100644
--- a/Modules/clinic/binascii.c.h
+++ b/Modules/clinic/binascii.c.h
@@ -189,7 +189,7 @@ binascii_rlecode_hqx(PyObject *module, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&data, 'C')) {
-        _PyArg_BadArgument("rlecode_hqx", "contiguous buffer", arg);
+        _PyArg_BadArgument("rlecode_hqx", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = binascii_rlecode_hqx_impl(module, &data);
@@ -225,7 +225,7 @@ binascii_b2a_hqx(PyObject *module, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&data, 'C')) {
-        _PyArg_BadArgument("b2a_hqx", "contiguous buffer", arg);
+        _PyArg_BadArgument("b2a_hqx", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = binascii_b2a_hqx_impl(module, &data);
@@ -261,7 +261,7 @@ binascii_rledecode_hqx(PyObject *module, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&data, 'C')) {
-        _PyArg_BadArgument("rledecode_hqx", "contiguous buffer", arg);
+        _PyArg_BadArgument("rledecode_hqx", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = binascii_rledecode_hqx_impl(module, &data);
@@ -295,8 +295,23 @@ binascii_crc_hqx(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     unsigned int crc;
     unsigned int _return_value;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*I:crc_hqx",
-        &data, &crc)) {
+    if (!_PyArg_CheckPositional("crc_hqx", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("crc_hqx", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    crc = (unsigned int)PyLong_AsUnsignedLongMask(args[1]);
+    if (crc == (unsigned int)-1 && PyErr_Occurred()) {
         goto exit;
     }
     _return_value = binascii_crc_hqx_impl(module, &data, crc);
@@ -334,10 +349,29 @@ binascii_crc32(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     unsigned int crc = 0;
     unsigned int _return_value;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*|I:crc32",
-        &data, &crc)) {
+    if (!_PyArg_CheckPositional("crc32", nargs, 1, 2)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("crc32", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    crc = (unsigned int)PyLong_AsUnsignedLongMask(args[1]);
+    if (crc == (unsigned int)-1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     _return_value = binascii_crc32_impl(module, &data, crc);
     if ((_return_value == (unsigned int)-1) && PyErr_Occurred()) {
         goto exit;
@@ -378,7 +412,7 @@ binascii_b2a_hex(PyObject *module, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&data, 'C')) {
-        _PyArg_BadArgument("b2a_hex", "contiguous buffer", arg);
+        _PyArg_BadArgument("b2a_hex", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = binascii_b2a_hex_impl(module, &data);
@@ -416,7 +450,7 @@ binascii_hexlify(PyObject *module, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&data, 'C')) {
-        _PyArg_BadArgument("hexlify", "contiguous buffer", arg);
+        _PyArg_BadArgument("hexlify", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = binascii_hexlify_impl(module, &data);
@@ -574,4 +608,4 @@ exit:
 
     return return_value;
 }
-/*[clinic end generated code: output=8ff0cb5717b15d1b input=a9049054013a1b77]*/
+/*[clinic end generated code: output=7210a01a718da4a0 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/cmathmodule.c.h b/Modules/clinic/cmathmodule.c.h
index 30378c7e841..cc1b8f2e21c 100644
--- a/Modules/clinic/cmathmodule.c.h
+++ b/Modules/clinic/cmathmodule.c.h
@@ -668,10 +668,18 @@ cmath_log(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_complex x;
     PyObject *y_obj = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "D|O:log",
-        &x, &y_obj)) {
+    if (!_PyArg_CheckPositional("log", nargs, 1, 2)) {
         goto exit;
     }
+    x = PyComplex_AsCComplex(args[0]);
+    if (PyErr_Occurred()) {
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    y_obj = args[1];
+skip_optional:
     return_value = cmath_log_impl(module, x, y_obj);
 
 exit:
@@ -755,8 +763,15 @@ cmath_rect(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     double r;
     double phi;
 
-    if (!_PyArg_ParseStack(args, nargs, "dd:rect",
-        &r, &phi)) {
+    if (!_PyArg_CheckPositional("rect", nargs, 2, 2)) {
+        goto exit;
+    }
+    r = PyFloat_AsDouble(args[0]);
+    if (PyErr_Occurred()) {
+        goto exit;
+    }
+    phi = PyFloat_AsDouble(args[1]);
+    if (PyErr_Occurred()) {
         goto exit;
     }
     return_value = cmath_rect_impl(module, r, phi);
@@ -902,4 +917,4 @@ cmath_isclose(PyObject *module, PyObject *const *args, Py_ssize_t nargs, PyObjec
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=50a105aa2bc5308f input=a9049054013a1b77]*/
+/*[clinic end generated code: output=86a365d23f34aaff input=a9049054013a1b77]*/
diff --git a/Modules/clinic/fcntlmodule.c.h b/Modules/clinic/fcntlmodule.c.h
index 7b5a280045c..024a44cfbf8 100644
--- a/Modules/clinic/fcntlmodule.c.h
+++ b/Modules/clinic/fcntlmodule.c.h
@@ -32,10 +32,26 @@ fcntl_fcntl(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int code;
     PyObject *arg = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "O&i|O:fcntl",
-        conv_descriptor, &fd, &code, &arg)) {
+    if (!_PyArg_CheckPositional("fcntl", nargs, 2, 3)) {
         goto exit;
     }
+    if (!conv_descriptor(args[0], &fd)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    code = _PyLong_AsInt(args[1]);
+    if (code == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    arg = args[2];
+skip_optional:
     return_value = fcntl_fcntl_impl(module, fd, code, arg);
 
 exit:
@@ -91,10 +107,33 @@ fcntl_ioctl(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *ob_arg = NULL;
     int mutate_arg = 1;
 
-    if (!_PyArg_ParseStack(args, nargs, "O&I|Op:ioctl",
-        conv_descriptor, &fd, &code, &ob_arg, &mutate_arg)) {
+    if (!_PyArg_CheckPositional("ioctl", nargs, 2, 4)) {
         goto exit;
     }
+    if (!conv_descriptor(args[0], &fd)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    code = (unsigned int)PyLong_AsUnsignedLongMask(args[1]);
+    if (code == (unsigned int)-1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    ob_arg = args[2];
+    if (nargs < 4) {
+        goto skip_optional;
+    }
+    mutate_arg = PyObject_IsTrue(args[3]);
+    if (mutate_arg < 0) {
+        goto exit;
+    }
+skip_optional:
     return_value = fcntl_ioctl_impl(module, fd, code, ob_arg, mutate_arg);
 
 exit:
@@ -123,8 +162,19 @@ fcntl_flock(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int fd;
     int code;
 
-    if (!_PyArg_ParseStack(args, nargs, "O&i:flock",
-        conv_descriptor, &fd, &code)) {
+    if (!_PyArg_CheckPositional("flock", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (!conv_descriptor(args[0], &fd)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    code = _PyLong_AsInt(args[1]);
+    if (code == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = fcntl_flock_impl(module, fd, code);
@@ -177,13 +227,45 @@ fcntl_lockf(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *startobj = NULL;
     int whence = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "O&i|OOi:lockf",
-        conv_descriptor, &fd, &code, &lenobj, &startobj, &whence)) {
+    if (!_PyArg_CheckPositional("lockf", nargs, 2, 5)) {
         goto exit;
     }
+    if (!conv_descriptor(args[0], &fd)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    code = _PyLong_AsInt(args[1]);
+    if (code == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    lenobj = args[2];
+    if (nargs < 4) {
+        goto skip_optional;
+    }
+    startobj = args[3];
+    if (nargs < 5) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[4])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    whence = _PyLong_AsInt(args[4]);
+    if (whence == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = fcntl_lockf_impl(module, fd, code, lenobj, startobj, whence);
 
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=fc1a781750750a14 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=e912d25e28362c52 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/itertoolsmodule.c.h b/Modules/clinic/itertoolsmodule.c.h
index b7d70a3492d..9fc429aa3c3 100644
--- a/Modules/clinic/itertoolsmodule.c.h
+++ b/Modules/clinic/itertoolsmodule.c.h
@@ -52,10 +52,15 @@ itertools__grouper(PyTypeObject *type, PyObject *args, PyObject *kwargs)
         !_PyArg_NoKeywords("_grouper", kwargs)) {
         goto exit;
     }
-    if (!PyArg_ParseTuple(args, "O!O:_grouper",
-        &groupby_type, &parent, &tgtkey)) {
+    if (!_PyArg_CheckPositional("_grouper", PyTuple_GET_SIZE(args), 2, 2)) {
         goto exit;
     }
+    if (!PyObject_TypeCheck(PyTuple_GET_ITEM(args, 0), &groupby_type)) {
+        _PyArg_BadArgument("_grouper", 1, (&groupby_type)->tp_name, PyTuple_GET_ITEM(args, 0));
+        goto exit;
+    }
+    parent = PyTuple_GET_ITEM(args, 0);
+    tgtkey = PyTuple_GET_ITEM(args, 1);
     return_value = itertools__grouper_impl(type, parent, tgtkey);
 
 exit:
@@ -84,10 +89,16 @@ itertools_teedataobject(PyTypeObject *type, PyObject *args, PyObject *kwargs)
         !_PyArg_NoKeywords("teedataobject", kwargs)) {
         goto exit;
     }
-    if (!PyArg_ParseTuple(args, "OO!O:teedataobject",
-        &it, &PyList_Type, &values, &next)) {
+    if (!_PyArg_CheckPositional("teedataobject", PyTuple_GET_SIZE(args), 3, 3)) {
         goto exit;
     }
+    it = PyTuple_GET_ITEM(args, 0);
+    if (!PyList_Check(PyTuple_GET_ITEM(args, 1))) {
+        _PyArg_BadArgument("teedataobject", 2, "list", PyTuple_GET_ITEM(args, 1));
+        goto exit;
+    }
+    values = PyTuple_GET_ITEM(args, 1);
+    next = PyTuple_GET_ITEM(args, 2);
     return_value = itertools_teedataobject_impl(type, it, values, next);
 
 exit:
@@ -143,10 +154,31 @@ itertools_tee(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *iterable;
     Py_ssize_t n = 2;
 
-    if (!_PyArg_ParseStack(args, nargs, "O|n:tee",
-        &iterable, &n)) {
+    if (!_PyArg_CheckPositional("tee", nargs, 1, 2)) {
         goto exit;
     }
+    iterable = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[1]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        n = ival;
+    }
+skip_optional:
     return_value = itertools_tee_impl(module, iterable, n);
 
 exit:
@@ -510,4 +542,4 @@ itertools_count(PyTypeObject *type, PyObject *args, PyObject *kwargs)
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=916251f891fa84b9 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=f289354f54e04c13 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/mathmodule.c.h b/Modules/clinic/mathmodule.c.h
index e436f5900c6..11657896875 100644
--- a/Modules/clinic/mathmodule.c.h
+++ b/Modules/clinic/mathmodule.c.h
@@ -139,10 +139,14 @@ math_ldexp(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     double x;
     PyObject *i;
 
-    if (!_PyArg_ParseStack(args, nargs, "dO:ldexp",
-        &x, &i)) {
+    if (!_PyArg_CheckPositional("ldexp", nargs, 2, 2)) {
         goto exit;
     }
+    x = PyFloat_AsDouble(args[0]);
+    if (PyErr_Occurred()) {
+        goto exit;
+    }
+    i = args[1];
     return_value = math_ldexp_impl(module, x, i);
 
 exit:
@@ -261,8 +265,15 @@ math_fmod(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     double x;
     double y;
 
-    if (!_PyArg_ParseStack(args, nargs, "dd:fmod",
-        &x, &y)) {
+    if (!_PyArg_CheckPositional("fmod", nargs, 2, 2)) {
+        goto exit;
+    }
+    x = PyFloat_AsDouble(args[0]);
+    if (PyErr_Occurred()) {
+        goto exit;
+    }
+    y = PyFloat_AsDouble(args[1]);
+    if (PyErr_Occurred()) {
         goto exit;
     }
     return_value = math_fmod_impl(module, x, y);
@@ -326,8 +337,15 @@ math_pow(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     double x;
     double y;
 
-    if (!_PyArg_ParseStack(args, nargs, "dd:pow",
-        &x, &y)) {
+    if (!_PyArg_CheckPositional("pow", nargs, 2, 2)) {
+        goto exit;
+    }
+    x = PyFloat_AsDouble(args[0]);
+    if (PyErr_Occurred()) {
+        goto exit;
+    }
+    y = PyFloat_AsDouble(args[1]);
+    if (PyErr_Occurred()) {
         goto exit;
     }
     return_value = math_pow_impl(module, x, y);
@@ -530,4 +548,4 @@ math_isclose(PyObject *module, PyObject *const *args, Py_ssize_t nargs, PyObject
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=da4b9940a5cb0188 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=2fe4fecd85585313 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/posixmodule.c.h b/Modules/clinic/posixmodule.c.h
index e310d99cf46..2c1ee97faf7 100644
--- a/Modules/clinic/posixmodule.c.h
+++ b/Modules/clinic/posixmodule.c.h
@@ -1658,10 +1658,13 @@ os_execv(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     path_t path = PATH_T_INITIALIZE("execv", "path", 0, 0);
     PyObject *argv;
 
-    if (!_PyArg_ParseStack(args, nargs, "O&O:execv",
-        path_converter, &path, &argv)) {
+    if (!_PyArg_CheckPositional("execv", nargs, 2, 2)) {
         goto exit;
     }
+    if (!path_converter(args[0], &path)) {
+        goto exit;
+    }
+    argv = args[1];
     return_value = os_execv_impl(module, &path, argv);
 
 exit:
@@ -1817,10 +1820,22 @@ os_spawnv(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     path_t path = PATH_T_INITIALIZE("spawnv", "path", 0, 0);
     PyObject *argv;
 
-    if (!_PyArg_ParseStack(args, nargs, "iO&O:spawnv",
-        &mode, path_converter, &path, &argv)) {
+    if (!_PyArg_CheckPositional("spawnv", nargs, 3, 3)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    mode = _PyLong_AsInt(args[0]);
+    if (mode == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (!path_converter(args[1], &path)) {
+        goto exit;
+    }
+    argv = args[2];
     return_value = os_spawnv_impl(module, mode, &path, argv);
 
 exit:
@@ -1865,10 +1880,23 @@ os_spawnve(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *argv;
     PyObject *env;
 
-    if (!_PyArg_ParseStack(args, nargs, "iO&OO:spawnve",
-        &mode, path_converter, &path, &argv, &env)) {
+    if (!_PyArg_CheckPositional("spawnve", nargs, 4, 4)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    mode = _PyLong_AsInt(args[0]);
+    if (mode == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (!path_converter(args[1], &path)) {
+        goto exit;
+    }
+    argv = args[2];
+    env = args[3];
     return_value = os_spawnve_impl(module, mode, &path, argv, env);
 
 exit:
@@ -2874,8 +2902,13 @@ os_setreuid(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     uid_t ruid;
     uid_t euid;
 
-    if (!_PyArg_ParseStack(args, nargs, "O&O&:setreuid",
-        _Py_Uid_Converter, &ruid, _Py_Uid_Converter, &euid)) {
+    if (!_PyArg_CheckPositional("setreuid", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (!_Py_Uid_Converter(args[0], &ruid)) {
+        goto exit;
+    }
+    if (!_Py_Uid_Converter(args[1], &euid)) {
         goto exit;
     }
     return_value = os_setreuid_impl(module, ruid, euid);
@@ -2907,8 +2940,13 @@ os_setregid(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     gid_t rgid;
     gid_t egid;
 
-    if (!_PyArg_ParseStack(args, nargs, "O&O&:setregid",
-        _Py_Gid_Converter, &rgid, _Py_Gid_Converter, &egid)) {
+    if (!_PyArg_CheckPositional("setregid", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (!_Py_Gid_Converter(args[0], &rgid)) {
+        goto exit;
+    }
+    if (!_Py_Gid_Converter(args[1], &egid)) {
         goto exit;
     }
     return_value = os_setregid_impl(module, rgid, egid);
@@ -3558,8 +3596,25 @@ os_closerange(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int fd_low;
     int fd_high;
 
-    if (!_PyArg_ParseStack(args, nargs, "ii:closerange",
-        &fd_low, &fd_high)) {
+    if (!_PyArg_CheckPositional("closerange", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd_low = _PyLong_AsInt(args[0]);
+    if (fd_low == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd_high = _PyLong_AsInt(args[1]);
+    if (fd_high == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = os_closerange_impl(module, fd_low, fd_high);
@@ -3672,8 +3727,28 @@ os_lockf(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int command;
     Py_off_t length;
 
-    if (!_PyArg_ParseStack(args, nargs, "iiO&:lockf",
-        &fd, &command, Py_off_t_converter, &length)) {
+    if (!_PyArg_CheckPositional("lockf", nargs, 3, 3)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd = _PyLong_AsInt(args[0]);
+    if (fd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    command = _PyLong_AsInt(args[1]);
+    if (command == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (!Py_off_t_converter(args[2], &length)) {
         goto exit;
     }
     return_value = os_lockf_impl(module, fd, command, length);
@@ -3708,8 +3783,28 @@ os_lseek(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int how;
     Py_off_t _return_value;
 
-    if (!_PyArg_ParseStack(args, nargs, "iO&i:lseek",
-        &fd, Py_off_t_converter, &position, &how)) {
+    if (!_PyArg_CheckPositional("lseek", nargs, 3, 3)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd = _PyLong_AsInt(args[0]);
+    if (fd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (!Py_off_t_converter(args[1], &position)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    how = _PyLong_AsInt(args[2]);
+    if (how == -1 && PyErr_Occurred()) {
         goto exit;
     }
     _return_value = os_lseek_impl(module, fd, position, how);
@@ -3741,10 +3836,35 @@ os_read(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int fd;
     Py_ssize_t length;
 
-    if (!_PyArg_ParseStack(args, nargs, "in:read",
-        &fd, &length)) {
+    if (!_PyArg_CheckPositional("read", nargs, 2, 2)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd = _PyLong_AsInt(args[0]);
+    if (fd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[1]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        length = ival;
+    }
     return_value = os_read_impl(module, fd, length);
 
 exit:
@@ -3781,10 +3901,19 @@ os_readv(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *buffers;
     Py_ssize_t _return_value;
 
-    if (!_PyArg_ParseStack(args, nargs, "iO:readv",
-        &fd, &buffers)) {
+    if (!_PyArg_CheckPositional("readv", nargs, 2, 2)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd = _PyLong_AsInt(args[0]);
+    if (fd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    buffers = args[1];
     _return_value = os_readv_impl(module, fd, buffers);
     if ((_return_value == -1) && PyErr_Occurred()) {
         goto exit;
@@ -3822,8 +3951,28 @@ os_pread(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int length;
     Py_off_t offset;
 
-    if (!_PyArg_ParseStack(args, nargs, "iiO&:pread",
-        &fd, &length, Py_off_t_converter, &offset)) {
+    if (!_PyArg_CheckPositional("pread", nargs, 3, 3)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd = _PyLong_AsInt(args[0]);
+    if (fd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    length = _PyLong_AsInt(args[1]);
+    if (length == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (!Py_off_t_converter(args[2], &offset)) {
         goto exit;
     }
     return_value = os_pread_impl(module, fd, length, offset);
@@ -3873,10 +4022,35 @@ os_preadv(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int flags = 0;
     Py_ssize_t _return_value;
 
-    if (!_PyArg_ParseStack(args, nargs, "iOO&|i:preadv",
-        &fd, &buffers, Py_off_t_converter, &offset, &flags)) {
+    if (!_PyArg_CheckPositional("preadv", nargs, 3, 4)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd = _PyLong_AsInt(args[0]);
+    if (fd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    buffers = args[1];
+    if (!Py_off_t_converter(args[2], &offset)) {
+        goto exit;
+    }
+    if (nargs < 4) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[3])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    flags = _PyLong_AsInt(args[3]);
+    if (flags == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     _return_value = os_preadv_impl(module, fd, buffers, offset, flags);
     if ((_return_value == -1) && PyErr_Occurred()) {
         goto exit;
@@ -3909,8 +4083,23 @@ os_write(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer data = {NULL, NULL};
     Py_ssize_t _return_value;
 
-    if (!_PyArg_ParseStack(args, nargs, "iy*:write",
-        &fd, &data)) {
+    if (!_PyArg_CheckPositional("write", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd = _PyLong_AsInt(args[0]);
+    if (fd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[1], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("write", 2, "contiguous buffer", args[1]);
         goto exit;
     }
     _return_value = os_write_impl(module, fd, &data);
@@ -3950,8 +4139,34 @@ os__fcopyfile(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int outfd;
     int flags;
 
-    if (!_PyArg_ParseStack(args, nargs, "iii:_fcopyfile",
-        &infd, &outfd, &flags)) {
+    if (!_PyArg_CheckPositional("_fcopyfile", nargs, 3, 3)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    infd = _PyLong_AsInt(args[0]);
+    if (infd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    outfd = _PyLong_AsInt(args[1]);
+    if (outfd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    flags = _PyLong_AsInt(args[2]);
+    if (flags == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = os__fcopyfile_impl(module, infd, outfd, flags);
@@ -4129,10 +4344,19 @@ os_writev(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *buffers;
     Py_ssize_t _return_value;
 
-    if (!_PyArg_ParseStack(args, nargs, "iO:writev",
-        &fd, &buffers)) {
+    if (!_PyArg_CheckPositional("writev", nargs, 2, 2)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd = _PyLong_AsInt(args[0]);
+    if (fd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    buffers = args[1];
     _return_value = os_writev_impl(module, fd, buffers);
     if ((_return_value == -1) && PyErr_Occurred()) {
         goto exit;
@@ -4172,8 +4396,26 @@ os_pwrite(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_off_t offset;
     Py_ssize_t _return_value;
 
-    if (!_PyArg_ParseStack(args, nargs, "iy*O&:pwrite",
-        &fd, &buffer, Py_off_t_converter, &offset)) {
+    if (!_PyArg_CheckPositional("pwrite", nargs, 3, 3)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd = _PyLong_AsInt(args[0]);
+    if (fd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[1], &buffer, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&buffer, 'C')) {
+        _PyArg_BadArgument("pwrite", 2, "contiguous buffer", args[1]);
+        goto exit;
+    }
+    if (!Py_off_t_converter(args[2], &offset)) {
         goto exit;
     }
     _return_value = os_pwrite_impl(module, fd, &buffer, offset);
@@ -4232,10 +4474,35 @@ os_pwritev(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int flags = 0;
     Py_ssize_t _return_value;
 
-    if (!_PyArg_ParseStack(args, nargs, "iOO&|i:pwritev",
-        &fd, &buffers, Py_off_t_converter, &offset, &flags)) {
+    if (!_PyArg_CheckPositional("pwritev", nargs, 3, 4)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd = _PyLong_AsInt(args[0]);
+    if (fd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    buffers = args[1];
+    if (!Py_off_t_converter(args[2], &offset)) {
+        goto exit;
+    }
+    if (nargs < 4) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[3])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    flags = _PyLong_AsInt(args[3]);
+    if (flags == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     _return_value = os_pwritev_impl(module, fd, buffers, offset, flags);
     if ((_return_value == -1) && PyErr_Occurred()) {
         goto exit;
@@ -4439,8 +4706,25 @@ os_makedev(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int minor;
     dev_t _return_value;
 
-    if (!_PyArg_ParseStack(args, nargs, "ii:makedev",
-        &major, &minor)) {
+    if (!_PyArg_CheckPositional("makedev", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    major = _PyLong_AsInt(args[0]);
+    if (major == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    minor = _PyLong_AsInt(args[1]);
+    if (minor == -1 && PyErr_Occurred()) {
         goto exit;
     }
     _return_value = os_makedev_impl(module, major, minor);
@@ -4476,8 +4760,19 @@ os_ftruncate(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int fd;
     Py_off_t length;
 
-    if (!_PyArg_ParseStack(args, nargs, "iO&:ftruncate",
-        &fd, Py_off_t_converter, &length)) {
+    if (!_PyArg_CheckPositional("ftruncate", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd = _PyLong_AsInt(args[0]);
+    if (fd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (!Py_off_t_converter(args[1], &length)) {
         goto exit;
     }
     return_value = os_ftruncate_impl(module, fd, length);
@@ -4555,8 +4850,22 @@ os_posix_fallocate(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_off_t offset;
     Py_off_t length;
 
-    if (!_PyArg_ParseStack(args, nargs, "iO&O&:posix_fallocate",
-        &fd, Py_off_t_converter, &offset, Py_off_t_converter, &length)) {
+    if (!_PyArg_CheckPositional("posix_fallocate", nargs, 3, 3)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd = _PyLong_AsInt(args[0]);
+    if (fd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (!Py_off_t_converter(args[1], &offset)) {
+        goto exit;
+    }
+    if (!Py_off_t_converter(args[2], &length)) {
         goto exit;
     }
     return_value = os_posix_fallocate_impl(module, fd, offset, length);
@@ -4599,8 +4908,31 @@ os_posix_fadvise(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_off_t length;
     int advice;
 
-    if (!_PyArg_ParseStack(args, nargs, "iO&O&i:posix_fadvise",
-        &fd, Py_off_t_converter, &offset, Py_off_t_converter, &length, &advice)) {
+    if (!_PyArg_CheckPositional("posix_fadvise", nargs, 4, 4)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd = _PyLong_AsInt(args[0]);
+    if (fd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (!Py_off_t_converter(args[1], &offset)) {
+        goto exit;
+    }
+    if (!Py_off_t_converter(args[2], &length)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[3])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    advice = _PyLong_AsInt(args[3]);
+    if (advice == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = os_posix_fadvise_impl(module, fd, offset, length, advice);
@@ -4632,10 +4964,25 @@ os_putenv(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *name;
     PyObject *value;
 
-    if (!_PyArg_ParseStack(args, nargs, "UU:putenv",
-        &name, &value)) {
+    if (!_PyArg_CheckPositional("putenv", nargs, 2, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("putenv", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    name = args[0];
+    if (!PyUnicode_Check(args[1])) {
+        _PyArg_BadArgument("putenv", 2, "str", args[1]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[1]) == -1) {
+        goto exit;
+    }
+    value = args[1];
     return_value = os_putenv_impl(module, name, value);
 
 exit:
@@ -4665,8 +5012,13 @@ os_putenv(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *name = NULL;
     PyObject *value = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "O&O&:putenv",
-        PyUnicode_FSConverter, &name, PyUnicode_FSConverter, &value)) {
+    if (!_PyArg_CheckPositional("putenv", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (!PyUnicode_FSConverter(args[0], &name)) {
+        goto exit;
+    }
+    if (!PyUnicode_FSConverter(args[1], &value)) {
         goto exit;
     }
     return_value = os_putenv_impl(module, name, value);
@@ -5208,8 +5560,19 @@ os_fpathconf(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int name;
     long _return_value;
 
-    if (!_PyArg_ParseStack(args, nargs, "iO&:fpathconf",
-        &fd, conv_path_confname, &name)) {
+    if (!_PyArg_CheckPositional("fpathconf", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd = _PyLong_AsInt(args[0]);
+    if (fd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (!conv_path_confname(args[1], &name)) {
         goto exit;
     }
     _return_value = os_fpathconf_impl(module, fd, name);
@@ -5496,8 +5859,16 @@ os_setresuid(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     uid_t euid;
     uid_t suid;
 
-    if (!_PyArg_ParseStack(args, nargs, "O&O&O&:setresuid",
-        _Py_Uid_Converter, &ruid, _Py_Uid_Converter, &euid, _Py_Uid_Converter, &suid)) {
+    if (!_PyArg_CheckPositional("setresuid", nargs, 3, 3)) {
+        goto exit;
+    }
+    if (!_Py_Uid_Converter(args[0], &ruid)) {
+        goto exit;
+    }
+    if (!_Py_Uid_Converter(args[1], &euid)) {
+        goto exit;
+    }
+    if (!_Py_Uid_Converter(args[2], &suid)) {
         goto exit;
     }
     return_value = os_setresuid_impl(module, ruid, euid, suid);
@@ -5530,8 +5901,16 @@ os_setresgid(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     gid_t egid;
     gid_t sgid;
 
-    if (!_PyArg_ParseStack(args, nargs, "O&O&O&:setresgid",
-        _Py_Gid_Converter, &rgid, _Py_Gid_Converter, &egid, _Py_Gid_Converter, &sgid)) {
+    if (!_PyArg_CheckPositional("setresgid", nargs, 3, 3)) {
+        goto exit;
+    }
+    if (!_Py_Gid_Converter(args[0], &rgid)) {
+        goto exit;
+    }
+    if (!_Py_Gid_Converter(args[1], &egid)) {
+        goto exit;
+    }
+    if (!_Py_Gid_Converter(args[2], &sgid)) {
         goto exit;
     }
     return_value = os_setresgid_impl(module, rgid, egid, sgid);
@@ -5898,8 +6277,25 @@ os_set_inheritable(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int fd;
     int inheritable;
 
-    if (!_PyArg_ParseStack(args, nargs, "ii:set_inheritable",
-        &fd, &inheritable)) {
+    if (!_PyArg_CheckPositional("set_inheritable", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd = _PyLong_AsInt(args[0]);
+    if (fd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    inheritable = _PyLong_AsInt(args[1]);
+    if (inheritable == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = os_set_inheritable_impl(module, fd, inheritable);
@@ -6046,8 +6442,25 @@ os_set_blocking(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int fd;
     int blocking;
 
-    if (!_PyArg_ParseStack(args, nargs, "ii:set_blocking",
-        &fd, &blocking)) {
+    if (!_PyArg_CheckPositional("set_blocking", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd = _PyLong_AsInt(args[0]);
+    if (fd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    blocking = _PyLong_AsInt(args[1]);
+    if (blocking == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = os_set_blocking_impl(module, fd, blocking);
@@ -6845,4 +7258,4 @@ exit:
 #ifndef OS_GETRANDOM_METHODDEF
     #define OS_GETRANDOM_METHODDEF
 #endif /* !defined(OS_GETRANDOM_METHODDEF) */
-/*[clinic end generated code: output=b02036b2a269b1db input=a9049054013a1b77]*/
+/*[clinic end generated code: output=febc1e16c9024e40 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/pwdmodule.c.h b/Modules/clinic/pwdmodule.c.h
index 9270be0f9bf..cf84ec959d5 100644
--- a/Modules/clinic/pwdmodule.c.h
+++ b/Modules/clinic/pwdmodule.c.h
@@ -34,7 +34,7 @@ pwd_getpwnam(PyObject *module, PyObject *arg)
     PyObject *name;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("getpwnam", "str", arg);
+        _PyArg_BadArgument("getpwnam", 0, "str", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg) == -1) {
@@ -74,4 +74,4 @@ pwd_getpwall(PyObject *module, PyObject *Py_UNUSED(ignored))
 #ifndef PWD_GETPWALL_METHODDEF
     #define PWD_GETPWALL_METHODDEF
 #endif /* !defined(PWD_GETPWALL_METHODDEF) */
-/*[clinic end generated code: output=9e86e23d6ad9cd08 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=f9412bdedc69706c input=a9049054013a1b77]*/
diff --git a/Modules/clinic/pyexpat.c.h b/Modules/clinic/pyexpat.c.h
index 1545485e9c5..3fe7b64e6f3 100644
--- a/Modules/clinic/pyexpat.c.h
+++ b/Modules/clinic/pyexpat.c.h
@@ -24,10 +24,23 @@ pyexpat_xmlparser_Parse(xmlparseobject *self, PyObject *const *args, Py_ssize_t
     PyObject *data;
     int isfinal = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "O|i:Parse",
-        &data, &isfinal)) {
+    if (!_PyArg_CheckPositional("Parse", nargs, 1, 2)) {
         goto exit;
     }
+    data = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    isfinal = _PyLong_AsInt(args[1]);
+    if (isfinal == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = pyexpat_xmlparser_Parse_impl(self, data, isfinal);
 
 exit:
@@ -62,7 +75,7 @@ pyexpat_xmlparser_SetBase(xmlparseobject *self, PyObject *arg)
     const char *base;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("SetBase", "str", arg);
+        _PyArg_BadArgument("SetBase", 0, "str", arg);
         goto exit;
     }
     Py_ssize_t base_length;
@@ -140,10 +153,44 @@ pyexpat_xmlparser_ExternalEntityParserCreate(xmlparseobject *self, PyObject *con
     const char *context;
     const char *encoding = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "z|s:ExternalEntityParserCreate",
-        &context, &encoding)) {
+    if (!_PyArg_CheckPositional("ExternalEntityParserCreate", nargs, 1, 2)) {
         goto exit;
     }
+    if (args[0] == Py_None) {
+        context = NULL;
+    }
+    else if (PyUnicode_Check(args[0])) {
+        Py_ssize_t context_length;
+        context = PyUnicode_AsUTF8AndSize(args[0], &context_length);
+        if (context == NULL) {
+            goto exit;
+        }
+        if (strlen(context) != (size_t)context_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+    }
+    else {
+        _PyArg_BadArgument("ExternalEntityParserCreate", 1, "str or None", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!PyUnicode_Check(args[1])) {
+        _PyArg_BadArgument("ExternalEntityParserCreate", 2, "str", args[1]);
+        goto exit;
+    }
+    Py_ssize_t encoding_length;
+    encoding = PyUnicode_AsUTF8AndSize(args[1], &encoding_length);
+    if (encoding == NULL) {
+        goto exit;
+    }
+    if (strlen(encoding) != (size_t)encoding_length) {
+        PyErr_SetString(PyExc_ValueError, "embedded null character");
+        goto exit;
+    }
+skip_optional:
     return_value = pyexpat_xmlparser_ExternalEntityParserCreate_impl(self, context, encoding);
 
 exit:
@@ -212,10 +259,17 @@ pyexpat_xmlparser_UseForeignDTD(xmlparseobject *self, PyObject *const *args, Py_
     PyObject *return_value = NULL;
     int flag = 1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|p:UseForeignDTD",
-        &flag)) {
+    if (!_PyArg_CheckPositional("UseForeignDTD", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    flag = PyObject_IsTrue(args[0]);
+    if (flag < 0) {
+        goto exit;
+    }
+skip_optional:
     return_value = pyexpat_xmlparser_UseForeignDTD_impl(self, flag);
 
 exit:
@@ -294,4 +348,4 @@ exit:
 #ifndef PYEXPAT_XMLPARSER_USEFOREIGNDTD_METHODDEF
     #define PYEXPAT_XMLPARSER_USEFOREIGNDTD_METHODDEF
 #endif /* !defined(PYEXPAT_XMLPARSER_USEFOREIGNDTD_METHODDEF) */
-/*[clinic end generated code: output=d3750256eb0da1cb input=a9049054013a1b77]*/
+/*[clinic end generated code: output=0f18b756d82b78a5 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/resource.c.h b/Modules/clinic/resource.c.h
index 0a66f8fd66f..80efb714bb6 100644
--- a/Modules/clinic/resource.c.h
+++ b/Modules/clinic/resource.c.h
@@ -84,10 +84,19 @@ resource_setrlimit(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int resource;
     PyObject *limits;
 
-    if (!_PyArg_ParseStack(args, nargs, "iO:setrlimit",
-        &resource, &limits)) {
+    if (!_PyArg_CheckPositional("setrlimit", nargs, 2, 2)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    resource = _PyLong_AsInt(args[0]);
+    if (resource == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    limits = args[1];
     return_value = resource_setrlimit_impl(module, resource, limits);
 
 exit:
@@ -169,4 +178,4 @@ exit:
 #ifndef RESOURCE_PRLIMIT_METHODDEF
     #define RESOURCE_PRLIMIT_METHODDEF
 #endif /* !defined(RESOURCE_PRLIMIT_METHODDEF) */
-/*[clinic end generated code: output=b16a9149639081fd input=a9049054013a1b77]*/
+/*[clinic end generated code: output=ef3034f291156a34 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/selectmodule.c.h b/Modules/clinic/selectmodule.c.h
index bb69d957c69..655e24c3533 100644
--- a/Modules/clinic/selectmodule.c.h
+++ b/Modules/clinic/selectmodule.c.h
@@ -82,10 +82,19 @@ select_poll_register(pollObject *self, PyObject *const *args, Py_ssize_t nargs)
     int fd;
     unsigned short eventmask = POLLIN | POLLPRI | POLLOUT;
 
-    if (!_PyArg_ParseStack(args, nargs, "O&|O&:register",
-        fildes_converter, &fd, _PyLong_UnsignedShort_Converter, &eventmask)) {
+    if (!_PyArg_CheckPositional("register", nargs, 1, 2)) {
         goto exit;
     }
+    if (!fildes_converter(args[0], &fd)) {
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!_PyLong_UnsignedShort_Converter(args[1], &eventmask)) {
+        goto exit;
+    }
+skip_optional:
     return_value = select_poll_register_impl(self, fd, eventmask);
 
 exit:
@@ -121,8 +130,13 @@ select_poll_modify(pollObject *self, PyObject *const *args, Py_ssize_t nargs)
     int fd;
     unsigned short eventmask;
 
-    if (!_PyArg_ParseStack(args, nargs, "O&O&:modify",
-        fildes_converter, &fd, _PyLong_UnsignedShort_Converter, &eventmask)) {
+    if (!_PyArg_CheckPositional("modify", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (!fildes_converter(args[0], &fd)) {
+        goto exit;
+    }
+    if (!_PyLong_UnsignedShort_Converter(args[1], &eventmask)) {
         goto exit;
     }
     return_value = select_poll_modify_impl(self, fd, eventmask);
@@ -228,10 +242,19 @@ select_devpoll_register(devpollObject *self, PyObject *const *args, Py_ssize_t n
     int fd;
     unsigned short eventmask = POLLIN | POLLPRI | POLLOUT;
 
-    if (!_PyArg_ParseStack(args, nargs, "O&|O&:register",
-        fildes_converter, &fd, _PyLong_UnsignedShort_Converter, &eventmask)) {
+    if (!_PyArg_CheckPositional("register", nargs, 1, 2)) {
         goto exit;
     }
+    if (!fildes_converter(args[0], &fd)) {
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!_PyLong_UnsignedShort_Converter(args[1], &eventmask)) {
+        goto exit;
+    }
+skip_optional:
     return_value = select_devpoll_register_impl(self, fd, eventmask);
 
 exit:
@@ -268,10 +291,19 @@ select_devpoll_modify(devpollObject *self, PyObject *const *args, Py_ssize_t nar
     int fd;
     unsigned short eventmask = POLLIN | POLLPRI | POLLOUT;
 
-    if (!_PyArg_ParseStack(args, nargs, "O&|O&:modify",
-        fildes_converter, &fd, _PyLong_UnsignedShort_Converter, &eventmask)) {
+    if (!_PyArg_CheckPositional("modify", nargs, 1, 2)) {
         goto exit;
     }
+    if (!fildes_converter(args[0], &fd)) {
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!_PyLong_UnsignedShort_Converter(args[1], &eventmask)) {
+        goto exit;
+    }
+skip_optional:
     return_value = select_devpoll_modify_impl(self, fd, eventmask);
 
 exit:
@@ -948,10 +980,24 @@ select_kqueue_control(kqueue_queue_Object *self, PyObject *const *args, Py_ssize
     int maxevents;
     PyObject *otimeout = Py_None;
 
-    if (!_PyArg_ParseStack(args, nargs, "Oi|O:control",
-        &changelist, &maxevents, &otimeout)) {
+    if (!_PyArg_CheckPositional("control", nargs, 2, 3)) {
         goto exit;
     }
+    changelist = args[0];
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    maxevents = _PyLong_AsInt(args[1]);
+    if (maxevents == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    otimeout = args[2];
+skip_optional:
     return_value = select_kqueue_control_impl(self, changelist, maxevents, otimeout);
 
 exit:
@@ -1059,4 +1105,4 @@ exit:
 #ifndef SELECT_KQUEUE_CONTROL_METHODDEF
     #define SELECT_KQUEUE_CONTROL_METHODDEF
 #endif /* !defined(SELECT_KQUEUE_CONTROL_METHODDEF) */
-/*[clinic end generated code: output=122a49f131cdd9d9 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=20da8f9c050e1b65 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/signalmodule.c.h b/Modules/clinic/signalmodule.c.h
index f3742262d86..bc46515cb43 100644
--- a/Modules/clinic/signalmodule.c.h
+++ b/Modules/clinic/signalmodule.c.h
@@ -125,10 +125,19 @@ signal_signal(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int signalnum;
     PyObject *handler;
 
-    if (!_PyArg_ParseStack(args, nargs, "iO:signal",
-        &signalnum, &handler)) {
+    if (!_PyArg_CheckPositional("signal", nargs, 2, 2)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    signalnum = _PyLong_AsInt(args[0]);
+    if (signalnum == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    handler = args[1];
     return_value = signal_signal_impl(module, signalnum, handler);
 
 exit:
@@ -234,8 +243,25 @@ signal_siginterrupt(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int signalnum;
     int flag;
 
-    if (!_PyArg_ParseStack(args, nargs, "ii:siginterrupt",
-        &signalnum, &flag)) {
+    if (!_PyArg_CheckPositional("siginterrupt", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    signalnum = _PyLong_AsInt(args[0]);
+    if (signalnum == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    flag = _PyLong_AsInt(args[1]);
+    if (flag == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = signal_siginterrupt_impl(module, signalnum, flag);
@@ -274,10 +300,24 @@ signal_setitimer(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *seconds;
     PyObject *interval = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "iO|O:setitimer",
-        &which, &seconds, &interval)) {
+    if (!_PyArg_CheckPositional("setitimer", nargs, 2, 3)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    which = _PyLong_AsInt(args[0]);
+    if (which == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    seconds = args[1];
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    interval = args[2];
+skip_optional:
     return_value = signal_setitimer_impl(module, which, seconds, interval);
 
 exit:
@@ -344,8 +384,19 @@ signal_pthread_sigmask(PyObject *module, PyObject *const *args, Py_ssize_t nargs
     int how;
     sigset_t mask;
 
-    if (!_PyArg_ParseStack(args, nargs, "iO&:pthread_sigmask",
-        &how, _Py_Sigset_Converter, &mask)) {
+    if (!_PyArg_CheckPositional("pthread_sigmask", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    how = _PyLong_AsInt(args[0]);
+    if (how == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (!_Py_Sigset_Converter(args[1], &mask)) {
         goto exit;
     }
     return_value = signal_pthread_sigmask_impl(module, how, mask);
@@ -498,10 +549,13 @@ signal_sigtimedwait(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     sigset_t sigset;
     PyObject *timeout_obj;
 
-    if (!_PyArg_ParseStack(args, nargs, "O&O:sigtimedwait",
-        _Py_Sigset_Converter, &sigset, &timeout_obj)) {
+    if (!_PyArg_CheckPositional("sigtimedwait", nargs, 2, 2)) {
         goto exit;
     }
+    if (!_Py_Sigset_Converter(args[0], &sigset)) {
+        goto exit;
+    }
+    timeout_obj = args[1];
     return_value = signal_sigtimedwait_impl(module, sigset, timeout_obj);
 
 exit:
@@ -532,8 +586,21 @@ signal_pthread_kill(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     unsigned long thread_id;
     int signalnum;
 
-    if (!_PyArg_ParseStack(args, nargs, "ki:pthread_kill",
-        &thread_id, &signalnum)) {
+    if (!_PyArg_CheckPositional("pthread_kill", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (!PyLong_Check(args[0])) {
+        _PyArg_BadArgument("pthread_kill", 1, "int", args[0]);
+        goto exit;
+    }
+    thread_id = PyLong_AsUnsignedLongMask(args[0]);
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    signalnum = _PyLong_AsInt(args[1]);
+    if (signalnum == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = signal_pthread_kill_impl(module, thread_id, signalnum);
@@ -591,4 +658,4 @@ exit:
 #ifndef SIGNAL_PTHREAD_KILL_METHODDEF
     #define SIGNAL_PTHREAD_KILL_METHODDEF
 #endif /* !defined(SIGNAL_PTHREAD_KILL_METHODDEF) */
-/*[clinic end generated code: output=365db4e807c26d4e input=a9049054013a1b77]*/
+/*[clinic end generated code: output=f0d3a5703581da76 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/spwdmodule.c.h b/Modules/clinic/spwdmodule.c.h
index a0a3e2e5ef8..e051e6eb658 100644
--- a/Modules/clinic/spwdmodule.c.h
+++ b/Modules/clinic/spwdmodule.c.h
@@ -25,7 +25,7 @@ spwd_getspnam(PyObject *module, PyObject *arg_)
     PyObject *arg;
 
     if (!PyUnicode_Check(arg_)) {
-        _PyArg_BadArgument("getspnam", "str", arg_);
+        _PyArg_BadArgument("getspnam", 0, "str", arg_);
         goto exit;
     }
     if (PyUnicode_READY(arg_) == -1) {
@@ -71,4 +71,4 @@ spwd_getspall(PyObject *module, PyObject *Py_UNUSED(ignored))
 #ifndef SPWD_GETSPALL_METHODDEF
     #define SPWD_GETSPALL_METHODDEF
 #endif /* !defined(SPWD_GETSPALL_METHODDEF) */
-/*[clinic end generated code: output=44a7c196d4b48f4e input=a9049054013a1b77]*/
+/*[clinic end generated code: output=2bbaa6bab1d9116e input=a9049054013a1b77]*/
diff --git a/Modules/clinic/symtablemodule.c.h b/Modules/clinic/symtablemodule.c.h
index b5e64e0313f..73e340bd462 100644
--- a/Modules/clinic/symtablemodule.c.h
+++ b/Modules/clinic/symtablemodule.c.h
@@ -23,8 +23,36 @@ _symtable_symtable(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *filename;
     const char *startstr;
 
-    if (!_PyArg_ParseStack(args, nargs, "sO&s:symtable",
-        &str, PyUnicode_FSDecoder, &filename, &startstr)) {
+    if (!_PyArg_CheckPositional("symtable", nargs, 3, 3)) {
+        goto exit;
+    }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("symtable", 1, "str", args[0]);
+        goto exit;
+    }
+    Py_ssize_t str_length;
+    str = PyUnicode_AsUTF8AndSize(args[0], &str_length);
+    if (str == NULL) {
+        goto exit;
+    }
+    if (strlen(str) != (size_t)str_length) {
+        PyErr_SetString(PyExc_ValueError, "embedded null character");
+        goto exit;
+    }
+    if (!PyUnicode_FSDecoder(args[1], &filename)) {
+        goto exit;
+    }
+    if (!PyUnicode_Check(args[2])) {
+        _PyArg_BadArgument("symtable", 3, "str", args[2]);
+        goto exit;
+    }
+    Py_ssize_t startstr_length;
+    startstr = PyUnicode_AsUTF8AndSize(args[2], &startstr_length);
+    if (startstr == NULL) {
+        goto exit;
+    }
+    if (strlen(startstr) != (size_t)startstr_length) {
+        PyErr_SetString(PyExc_ValueError, "embedded null character");
         goto exit;
     }
     return_value = _symtable_symtable_impl(module, str, filename, startstr);
@@ -32,4 +60,4 @@ _symtable_symtable(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=52ece07dd0e7a113 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=be1cca59de019984 input=a9049054013a1b77]*/
diff --git a/Modules/clinic/unicodedata.c.h b/Modules/clinic/unicodedata.c.h
index 9e8d261bda5..8ca0881efcf 100644
--- a/Modules/clinic/unicodedata.c.h
+++ b/Modules/clinic/unicodedata.c.h
@@ -26,10 +26,26 @@ unicodedata_UCD_decimal(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
     int chr;
     PyObject *default_value = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "C|O:decimal",
-        &chr, &default_value)) {
+    if (!_PyArg_CheckPositional("decimal", nargs, 1, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("decimal", 1, "a unicode character", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0])) {
+        goto exit;
+    }
+    if (PyUnicode_GET_LENGTH(args[0]) != 1) {
+        _PyArg_BadArgument("decimal", 1, "a unicode character", args[0]);
+        goto exit;
+    }
+    chr = PyUnicode_READ_CHAR(args[0], 0);
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    default_value = args[1];
+skip_optional:
     return_value = unicodedata_UCD_decimal_impl(self, chr, default_value);
 
 exit:
@@ -59,10 +75,26 @@ unicodedata_UCD_digit(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
     int chr;
     PyObject *default_value = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "C|O:digit",
-        &chr, &default_value)) {
+    if (!_PyArg_CheckPositional("digit", nargs, 1, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("digit", 1, "a unicode character", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0])) {
+        goto exit;
+    }
+    if (PyUnicode_GET_LENGTH(args[0]) != 1) {
+        _PyArg_BadArgument("digit", 1, "a unicode character", args[0]);
+        goto exit;
+    }
+    chr = PyUnicode_READ_CHAR(args[0], 0);
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    default_value = args[1];
+skip_optional:
     return_value = unicodedata_UCD_digit_impl(self, chr, default_value);
 
 exit:
@@ -93,10 +125,26 @@ unicodedata_UCD_numeric(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
     int chr;
     PyObject *default_value = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "C|O:numeric",
-        &chr, &default_value)) {
+    if (!_PyArg_CheckPositional("numeric", nargs, 1, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("numeric", 1, "a unicode character", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0])) {
+        goto exit;
+    }
+    if (PyUnicode_GET_LENGTH(args[0]) != 1) {
+        _PyArg_BadArgument("numeric", 1, "a unicode character", args[0]);
+        goto exit;
+    }
+    chr = PyUnicode_READ_CHAR(args[0], 0);
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    default_value = args[1];
+skip_optional:
     return_value = unicodedata_UCD_numeric_impl(self, chr, default_value);
 
 exit:
@@ -122,14 +170,14 @@ unicodedata_UCD_category(PyObject *self, PyObject *arg)
     int chr;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("category", "a unicode character", arg);
+        _PyArg_BadArgument("category", 0, "a unicode character", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg)) {
         goto exit;
     }
     if (PyUnicode_GET_LENGTH(arg) != 1) {
-        _PyArg_BadArgument("category", "a unicode character", arg);
+        _PyArg_BadArgument("category", 0, "a unicode character", arg);
         goto exit;
     }
     chr = PyUnicode_READ_CHAR(arg, 0);
@@ -160,14 +208,14 @@ unicodedata_UCD_bidirectional(PyObject *self, PyObject *arg)
     int chr;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("bidirectional", "a unicode character", arg);
+        _PyArg_BadArgument("bidirectional", 0, "a unicode character", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg)) {
         goto exit;
     }
     if (PyUnicode_GET_LENGTH(arg) != 1) {
-        _PyArg_BadArgument("bidirectional", "a unicode character", arg);
+        _PyArg_BadArgument("bidirectional", 0, "a unicode character", arg);
         goto exit;
     }
     chr = PyUnicode_READ_CHAR(arg, 0);
@@ -199,14 +247,14 @@ unicodedata_UCD_combining(PyObject *self, PyObject *arg)
     int _return_value;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("combining", "a unicode character", arg);
+        _PyArg_BadArgument("combining", 0, "a unicode character", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg)) {
         goto exit;
     }
     if (PyUnicode_GET_LENGTH(arg) != 1) {
-        _PyArg_BadArgument("combining", "a unicode character", arg);
+        _PyArg_BadArgument("combining", 0, "a unicode character", arg);
         goto exit;
     }
     chr = PyUnicode_READ_CHAR(arg, 0);
@@ -243,14 +291,14 @@ unicodedata_UCD_mirrored(PyObject *self, PyObject *arg)
     int _return_value;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("mirrored", "a unicode character", arg);
+        _PyArg_BadArgument("mirrored", 0, "a unicode character", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg)) {
         goto exit;
     }
     if (PyUnicode_GET_LENGTH(arg) != 1) {
-        _PyArg_BadArgument("mirrored", "a unicode character", arg);
+        _PyArg_BadArgument("mirrored", 0, "a unicode character", arg);
         goto exit;
     }
     chr = PyUnicode_READ_CHAR(arg, 0);
@@ -283,14 +331,14 @@ unicodedata_UCD_east_asian_width(PyObject *self, PyObject *arg)
     int chr;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("east_asian_width", "a unicode character", arg);
+        _PyArg_BadArgument("east_asian_width", 0, "a unicode character", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg)) {
         goto exit;
     }
     if (PyUnicode_GET_LENGTH(arg) != 1) {
-        _PyArg_BadArgument("east_asian_width", "a unicode character", arg);
+        _PyArg_BadArgument("east_asian_width", 0, "a unicode character", arg);
         goto exit;
     }
     chr = PyUnicode_READ_CHAR(arg, 0);
@@ -321,14 +369,14 @@ unicodedata_UCD_decomposition(PyObject *self, PyObject *arg)
     int chr;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("decomposition", "a unicode character", arg);
+        _PyArg_BadArgument("decomposition", 0, "a unicode character", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg)) {
         goto exit;
     }
     if (PyUnicode_GET_LENGTH(arg) != 1) {
-        _PyArg_BadArgument("decomposition", "a unicode character", arg);
+        _PyArg_BadArgument("decomposition", 0, "a unicode character", arg);
         goto exit;
     }
     chr = PyUnicode_READ_CHAR(arg, 0);
@@ -360,10 +408,25 @@ unicodedata_UCD_is_normalized(PyObject *self, PyObject *const *args, Py_ssize_t
     PyObject *form;
     PyObject *input;
 
-    if (!_PyArg_ParseStack(args, nargs, "UU:is_normalized",
-        &form, &input)) {
+    if (!_PyArg_CheckPositional("is_normalized", nargs, 2, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("is_normalized", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    form = args[0];
+    if (!PyUnicode_Check(args[1])) {
+        _PyArg_BadArgument("is_normalized", 2, "str", args[1]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[1]) == -1) {
+        goto exit;
+    }
+    input = args[1];
     return_value = unicodedata_UCD_is_normalized_impl(self, form, input);
 
 exit:
@@ -392,10 +455,25 @@ unicodedata_UCD_normalize(PyObject *self, PyObject *const *args, Py_ssize_t narg
     PyObject *form;
     PyObject *input;
 
-    if (!_PyArg_ParseStack(args, nargs, "UU:normalize",
-        &form, &input)) {
+    if (!_PyArg_CheckPositional("normalize", nargs, 2, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("normalize", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    form = args[0];
+    if (!PyUnicode_Check(args[1])) {
+        _PyArg_BadArgument("normalize", 2, "str", args[1]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[1]) == -1) {
+        goto exit;
+    }
+    input = args[1];
     return_value = unicodedata_UCD_normalize_impl(self, form, input);
 
 exit:
@@ -424,10 +502,26 @@ unicodedata_UCD_name(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
     int chr;
     PyObject *default_value = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "C|O:name",
-        &chr, &default_value)) {
+    if (!_PyArg_CheckPositional("name", nargs, 1, 2)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("name", 1, "a unicode character", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0])) {
+        goto exit;
+    }
+    if (PyUnicode_GET_LENGTH(args[0]) != 1) {
+        _PyArg_BadArgument("name", 1, "a unicode character", args[0]);
+        goto exit;
+    }
+    chr = PyUnicode_READ_CHAR(args[0], 0);
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    default_value = args[1];
+skip_optional:
     return_value = unicodedata_UCD_name_impl(self, chr, default_value);
 
 exit:
@@ -465,4 +559,4 @@ unicodedata_UCD_lookup(PyObject *self, PyObject *arg)
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=709241b99d010896 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=0fc850fe5b6b312c input=a9049054013a1b77]*/
diff --git a/Modules/clinic/zlibmodule.c.h b/Modules/clinic/zlibmodule.c.h
index 87ad1ea0029..8e5f96aa143 100644
--- a/Modules/clinic/zlibmodule.c.h
+++ b/Modules/clinic/zlibmodule.c.h
@@ -219,7 +219,7 @@ zlib_Compress_compress(compobject *self, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&data, 'C')) {
-        _PyArg_BadArgument("compress", "contiguous buffer", arg);
+        _PyArg_BadArgument("compress", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = zlib_Compress_compress_impl(self, &data);
@@ -305,10 +305,22 @@ zlib_Compress_flush(compobject *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     int mode = Z_FINISH;
 
-    if (!_PyArg_ParseStack(args, nargs, "|i:flush",
-        &mode)) {
+    if (!_PyArg_CheckPositional("flush", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    mode = _PyLong_AsInt(args[0]);
+    if (mode == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = zlib_Compress_flush_impl(self, mode);
 
 exit:
@@ -446,10 +458,16 @@ zlib_Decompress_flush(compobject *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t length = DEF_BUF_SIZE;
 
-    if (!_PyArg_ParseStack(args, nargs, "|O&:flush",
-        ssize_t_converter, &length)) {
+    if (!_PyArg_CheckPositional("flush", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (!ssize_t_converter(args[0], &length)) {
+        goto exit;
+    }
+skip_optional:
     return_value = zlib_Decompress_flush_impl(self, length);
 
 exit:
@@ -480,10 +498,29 @@ zlib_adler32(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer data = {NULL, NULL};
     unsigned int value = 1;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*|I:adler32",
-        &data, &value)) {
+    if (!_PyArg_CheckPositional("adler32", nargs, 1, 2)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("adler32", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    value = (unsigned int)PyLong_AsUnsignedLongMask(args[1]);
+    if (value == (unsigned int)-1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = zlib_adler32_impl(module, &data, value);
 
 exit:
@@ -519,10 +556,29 @@ zlib_crc32(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer data = {NULL, NULL};
     unsigned int value = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*|I:crc32",
-        &data, &value)) {
+    if (!_PyArg_CheckPositional("crc32", nargs, 1, 2)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &data, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&data, 'C')) {
+        _PyArg_BadArgument("crc32", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    value = (unsigned int)PyLong_AsUnsignedLongMask(args[1]);
+    if (value == (unsigned int)-1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = zlib_crc32_impl(module, &data, value);
 
 exit:
@@ -557,4 +613,4 @@ exit:
 #ifndef ZLIB_DECOMPRESS___DEEPCOPY___METHODDEF
     #define ZLIB_DECOMPRESS___DEEPCOPY___METHODDEF
 #endif /* !defined(ZLIB_DECOMPRESS___DEEPCOPY___METHODDEF) */
-/*[clinic end generated code: output=bea1e3c64573d9fd input=a9049054013a1b77]*/
+/*[clinic end generated code: output=b3acec2384f18782 input=a9049054013a1b77]*/
diff --git a/Objects/clinic/bytearrayobject.c.h b/Objects/clinic/bytearrayobject.c.h
index ec35eefa774..2d7c7420077 100644
--- a/Objects/clinic/bytearrayobject.c.h
+++ b/Objects/clinic/bytearrayobject.c.h
@@ -100,8 +100,21 @@ bytearray_maketrans(void *null, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer frm = {NULL, NULL};
     Py_buffer to = {NULL, NULL};
 
-    if (!_PyArg_ParseStack(args, nargs, "y*y*:maketrans",
-        &frm, &to)) {
+    if (!_PyArg_CheckPositional("maketrans", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &frm, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&frm, 'C')) {
+        _PyArg_BadArgument("maketrans", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[1], &to, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&to, 'C')) {
+        _PyArg_BadArgument("maketrans", 2, "contiguous buffer", args[1]);
         goto exit;
     }
     return_value = bytearray_maketrans_impl(&frm, &to);
@@ -147,10 +160,44 @@ bytearray_replace(PyByteArrayObject *self, PyObject *const *args, Py_ssize_t nar
     Py_buffer new = {NULL, NULL};
     Py_ssize_t count = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*y*|n:replace",
-        &old, &new, &count)) {
+    if (!_PyArg_CheckPositional("replace", nargs, 2, 3)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &old, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&old, 'C')) {
+        _PyArg_BadArgument("replace", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[1], &new, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&new, 'C')) {
+        _PyArg_BadArgument("replace", 2, "contiguous buffer", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[2]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        count = ival;
+    }
+skip_optional:
     return_value = bytearray_replace_impl(self, &old, &new, count);
 
 exit:
@@ -323,8 +370,27 @@ bytearray_insert(PyByteArrayObject *self, PyObject *const *args, Py_ssize_t narg
     Py_ssize_t index;
     int item;
 
-    if (!_PyArg_ParseStack(args, nargs, "nO&:insert",
-        &index, _getbytevalue, &item)) {
+    if (!_PyArg_CheckPositional("insert", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        index = ival;
+    }
+    if (!_getbytevalue(args[1], &item)) {
         goto exit;
     }
     return_value = bytearray_insert_impl(self, index, item);
@@ -399,10 +465,30 @@ bytearray_pop(PyByteArrayObject *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t index = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|n:pop",
-        &index)) {
+    if (!_PyArg_CheckPositional("pop", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        index = ival;
+    }
+skip_optional:
     return_value = bytearray_pop_impl(self, index);
 
 exit:
@@ -641,7 +727,7 @@ bytearray_fromhex(PyTypeObject *type, PyObject *arg)
     PyObject *string;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("fromhex", "str", arg);
+        _PyArg_BadArgument("fromhex", 0, "str", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg) == -1) {
@@ -690,10 +776,22 @@ bytearray_reduce_ex(PyByteArrayObject *self, PyObject *const *args, Py_ssize_t n
     PyObject *return_value = NULL;
     int proto = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "|i:__reduce_ex__",
-        &proto)) {
+    if (!_PyArg_CheckPositional("__reduce_ex__", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    proto = _PyLong_AsInt(args[0]);
+    if (proto == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = bytearray_reduce_ex_impl(self, proto);
 
 exit:
@@ -717,4 +815,4 @@ bytearray_sizeof(PyByteArrayObject *self, PyObject *Py_UNUSED(ignored))
 {
     return bytearray_sizeof_impl(self);
 }
-/*[clinic end generated code: output=cd3e13a1905a473c input=a9049054013a1b77]*/
+/*[clinic end generated code: output=010e281b823d7df1 input=a9049054013a1b77]*/
diff --git a/Objects/clinic/bytesobject.c.h b/Objects/clinic/bytesobject.c.h
index 1345b644d17..4e754d91af3 100644
--- a/Objects/clinic/bytesobject.c.h
+++ b/Objects/clinic/bytesobject.c.h
@@ -70,7 +70,7 @@ bytes_partition(PyBytesObject *self, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&sep, 'C')) {
-        _PyArg_BadArgument("partition", "contiguous buffer", arg);
+        _PyArg_BadArgument("partition", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = bytes_partition_impl(self, &sep);
@@ -113,7 +113,7 @@ bytes_rpartition(PyBytesObject *self, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&sep, 'C')) {
-        _PyArg_BadArgument("rpartition", "contiguous buffer", arg);
+        _PyArg_BadArgument("rpartition", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = bytes_rpartition_impl(self, &sep);
@@ -338,8 +338,21 @@ bytes_maketrans(void *null, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer frm = {NULL, NULL};
     Py_buffer to = {NULL, NULL};
 
-    if (!_PyArg_ParseStack(args, nargs, "y*y*:maketrans",
-        &frm, &to)) {
+    if (!_PyArg_CheckPositional("maketrans", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[0], &frm, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&frm, 'C')) {
+        _PyArg_BadArgument("maketrans", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[1], &to, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&to, 'C')) {
+        _PyArg_BadArgument("maketrans", 2, "contiguous buffer", args[1]);
         goto exit;
     }
     return_value = bytes_maketrans_impl(&frm, &to);
@@ -385,10 +398,44 @@ bytes_replace(PyBytesObject *self, PyObject *const *args, Py_ssize_t nargs)
     Py_buffer new = {NULL, NULL};
     Py_ssize_t count = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "y*y*|n:replace",
-        &old, &new, &count)) {
+    if (!_PyArg_CheckPositional("replace", nargs, 2, 3)) {
         goto exit;
     }
+    if (PyObject_GetBuffer(args[0], &old, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&old, 'C')) {
+        _PyArg_BadArgument("replace", 1, "contiguous buffer", args[0]);
+        goto exit;
+    }
+    if (PyObject_GetBuffer(args[1], &new, PyBUF_SIMPLE) != 0) {
+        goto exit;
+    }
+    if (!PyBuffer_IsContiguous(&new, 'C')) {
+        _PyArg_BadArgument("replace", 2, "contiguous buffer", args[1]);
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[2]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        count = ival;
+    }
+skip_optional:
     return_value = bytes_replace_impl(self, &old, &new, count);
 
 exit:
@@ -500,7 +547,7 @@ bytes_fromhex(PyTypeObject *type, PyObject *arg)
     PyObject *string;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("fromhex", "str", arg);
+        _PyArg_BadArgument("fromhex", 0, "str", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg) == -1) {
@@ -512,4 +559,4 @@ bytes_fromhex(PyTypeObject *type, PyObject *arg)
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=dc9aa04f0007ab11 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=810c8dfc72520ca4 input=a9049054013a1b77]*/
diff --git a/Objects/clinic/floatobject.c.h b/Objects/clinic/floatobject.c.h
index 28b24d0a093..741ca3bac5b 100644
--- a/Objects/clinic/floatobject.c.h
+++ b/Objects/clinic/floatobject.c.h
@@ -229,7 +229,7 @@ float___getformat__(PyTypeObject *type, PyObject *arg)
     const char *typestr;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("__getformat__", "str", arg);
+        _PyArg_BadArgument("__getformat__", 0, "str", arg);
         goto exit;
     }
     Py_ssize_t typestr_length;
@@ -279,8 +279,33 @@ float___set_format__(PyTypeObject *type, PyObject *const *args, Py_ssize_t nargs
     const char *typestr;
     const char *fmt;
 
-    if (!_PyArg_ParseStack(args, nargs, "ss:__set_format__",
-        &typestr, &fmt)) {
+    if (!_PyArg_CheckPositional("__set_format__", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("__set_format__", 1, "str", args[0]);
+        goto exit;
+    }
+    Py_ssize_t typestr_length;
+    typestr = PyUnicode_AsUTF8AndSize(args[0], &typestr_length);
+    if (typestr == NULL) {
+        goto exit;
+    }
+    if (strlen(typestr) != (size_t)typestr_length) {
+        PyErr_SetString(PyExc_ValueError, "embedded null character");
+        goto exit;
+    }
+    if (!PyUnicode_Check(args[1])) {
+        _PyArg_BadArgument("__set_format__", 2, "str", args[1]);
+        goto exit;
+    }
+    Py_ssize_t fmt_length;
+    fmt = PyUnicode_AsUTF8AndSize(args[1], &fmt_length);
+    if (fmt == NULL) {
+        goto exit;
+    }
+    if (strlen(fmt) != (size_t)fmt_length) {
+        PyErr_SetString(PyExc_ValueError, "embedded null character");
         goto exit;
     }
     return_value = float___set_format___impl(type, typestr, fmt);
@@ -308,7 +333,7 @@ float___format__(PyObject *self, PyObject *arg)
     PyObject *format_spec;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("__format__", "str", arg);
+        _PyArg_BadArgument("__format__", 0, "str", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg) == -1) {
@@ -320,4 +345,4 @@ float___format__(PyObject *self, PyObject *arg)
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=e8f8be828462d58b input=a9049054013a1b77]*/
+/*[clinic end generated code: output=2631a60701a8f7d4 input=a9049054013a1b77]*/
diff --git a/Objects/clinic/listobject.c.h b/Objects/clinic/listobject.c.h
index 0097481dbae..36174586141 100644
--- a/Objects/clinic/listobject.c.h
+++ b/Objects/clinic/listobject.c.h
@@ -21,10 +21,27 @@ list_insert(PyListObject *self, PyObject *const *args, Py_ssize_t nargs)
     Py_ssize_t index;
     PyObject *object;
 
-    if (!_PyArg_ParseStack(args, nargs, "nO:insert",
-        &index, &object)) {
+    if (!_PyArg_CheckPositional("insert", nargs, 2, 2)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        index = ival;
+    }
+    object = args[1];
     return_value = list_insert_impl(self, index, object);
 
 exit:
@@ -105,10 +122,30 @@ list_pop(PyListObject *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     Py_ssize_t index = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "|n:pop",
-        &index)) {
+    if (!_PyArg_CheckPositional("pop", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        index = ival;
+    }
+skip_optional:
     return_value = list_pop_impl(self, index);
 
 exit:
@@ -187,10 +224,23 @@ list_index(PyListObject *self, PyObject *const *args, Py_ssize_t nargs)
     Py_ssize_t start = 0;
     Py_ssize_t stop = PY_SSIZE_T_MAX;
 
-    if (!_PyArg_ParseStack(args, nargs, "O|O&O&:index",
-        &value, _PyEval_SliceIndexNotNone, &start, _PyEval_SliceIndexNotNone, &stop)) {
+    if (!_PyArg_CheckPositional("index", nargs, 1, 3)) {
         goto exit;
     }
+    value = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!_PyEval_SliceIndexNotNone(args[1], &start)) {
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (!_PyEval_SliceIndexNotNone(args[2], &stop)) {
+        goto exit;
+    }
+skip_optional:
     return_value = list_index_impl(self, value, start, stop);
 
 exit:
@@ -285,4 +335,4 @@ list___reversed__(PyListObject *self, PyObject *Py_UNUSED(ignored))
 {
     return list___reversed___impl(self);
 }
-/*[clinic end generated code: output=652ae4ee63a9de71 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=1f641f5aef3f886f input=a9049054013a1b77]*/
diff --git a/Objects/clinic/longobject.c.h b/Objects/clinic/longobject.c.h
index 27cdf9e6050..67700239ff8 100644
--- a/Objects/clinic/longobject.c.h
+++ b/Objects/clinic/longobject.c.h
@@ -59,7 +59,7 @@ int___format__(PyObject *self, PyObject *arg)
     PyObject *format_spec;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("__format__", "str", arg);
+        _PyArg_BadArgument("__format__", 0, "str", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg) == -1) {
@@ -244,4 +244,4 @@ int_from_bytes(PyTypeObject *type, PyObject *const *args, Py_ssize_t nargs, PyOb
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=7436b5f4decdcf9d input=a9049054013a1b77]*/
+/*[clinic end generated code: output=3b91cda9d83abaa2 input=a9049054013a1b77]*/
diff --git a/Objects/clinic/tupleobject.c.h b/Objects/clinic/tupleobject.c.h
index 67d9f340e08..0096f0cd0f6 100644
--- a/Objects/clinic/tupleobject.c.h
+++ b/Objects/clinic/tupleobject.c.h
@@ -25,10 +25,23 @@ tuple_index(PyTupleObject *self, PyObject *const *args, Py_ssize_t nargs)
     Py_ssize_t start = 0;
     Py_ssize_t stop = PY_SSIZE_T_MAX;
 
-    if (!_PyArg_ParseStack(args, nargs, "O|O&O&:index",
-        &value, _PyEval_SliceIndexNotNone, &start, _PyEval_SliceIndexNotNone, &stop)) {
+    if (!_PyArg_CheckPositional("index", nargs, 1, 3)) {
         goto exit;
     }
+    value = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!_PyEval_SliceIndexNotNone(args[1], &start)) {
+        goto exit;
+    }
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (!_PyEval_SliceIndexNotNone(args[2], &stop)) {
+        goto exit;
+    }
+skip_optional:
     return_value = tuple_index_impl(self, value, start, stop);
 
 exit:
@@ -95,4 +108,4 @@ tuple___getnewargs__(PyTupleObject *self, PyObject *Py_UNUSED(ignored))
 {
     return tuple___getnewargs___impl(self);
 }
-/*[clinic end generated code: output=0a6ebd2d16b09c5d input=a9049054013a1b77]*/
+/*[clinic end generated code: output=5312868473a41cfe input=a9049054013a1b77]*/
diff --git a/Objects/clinic/typeobject.c.h b/Objects/clinic/typeobject.c.h
index 115a21807be..fbe1261fb5a 100644
--- a/Objects/clinic/typeobject.c.h
+++ b/Objects/clinic/typeobject.c.h
@@ -200,7 +200,7 @@ object___format__(PyObject *self, PyObject *arg)
     PyObject *format_spec;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("__format__", "str", arg);
+        _PyArg_BadArgument("__format__", 0, "str", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg) == -1) {
@@ -248,4 +248,4 @@ object___dir__(PyObject *self, PyObject *Py_UNUSED(ignored))
 {
     return object___dir___impl(self);
 }
-/*[clinic end generated code: output=09f3453839e60136 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=ea5734413064fa7e input=a9049054013a1b77]*/
diff --git a/Objects/clinic/unicodeobject.c.h b/Objects/clinic/unicodeobject.c.h
index 744a6ebd23f..21e54f1011c 100644
--- a/Objects/clinic/unicodeobject.c.h
+++ b/Objects/clinic/unicodeobject.c.h
@@ -83,10 +83,33 @@ unicode_center(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
     Py_ssize_t width;
     Py_UCS4 fillchar = ' ';
 
-    if (!_PyArg_ParseStack(args, nargs, "n|O&:center",
-        &width, convert_uc, &fillchar)) {
+    if (!_PyArg_CheckPositional("center", nargs, 1, 2)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        width = ival;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!convert_uc(args[1], &fillchar)) {
+        goto exit;
+    }
+skip_optional:
     return_value = unicode_center_impl(self, width, fillchar);
 
 exit:
@@ -452,10 +475,33 @@ unicode_ljust(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
     Py_ssize_t width;
     Py_UCS4 fillchar = ' ';
 
-    if (!_PyArg_ParseStack(args, nargs, "n|O&:ljust",
-        &width, convert_uc, &fillchar)) {
+    if (!_PyArg_CheckPositional("ljust", nargs, 1, 2)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        width = ival;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!convert_uc(args[1], &fillchar)) {
+        goto exit;
+    }
+skip_optional:
     return_value = unicode_ljust_impl(self, width, fillchar);
 
 exit:
@@ -601,10 +647,46 @@ unicode_replace(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
     PyObject *new;
     Py_ssize_t count = -1;
 
-    if (!_PyArg_ParseStack(args, nargs, "UU|n:replace",
-        &old, &new, &count)) {
+    if (!_PyArg_CheckPositional("replace", nargs, 2, 3)) {
         goto exit;
     }
+    if (!PyUnicode_Check(args[0])) {
+        _PyArg_BadArgument("replace", 1, "str", args[0]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[0]) == -1) {
+        goto exit;
+    }
+    old = args[0];
+    if (!PyUnicode_Check(args[1])) {
+        _PyArg_BadArgument("replace", 2, "str", args[1]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[1]) == -1) {
+        goto exit;
+    }
+    new = args[1];
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[2]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        count = ival;
+    }
+skip_optional:
     return_value = unicode_replace_impl(self, old, new, count);
 
 exit:
@@ -632,10 +714,33 @@ unicode_rjust(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
     Py_ssize_t width;
     Py_UCS4 fillchar = ' ';
 
-    if (!_PyArg_ParseStack(args, nargs, "n|O&:rjust",
-        &width, convert_uc, &fillchar)) {
+    if (!_PyArg_CheckPositional("rjust", nargs, 1, 2)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        width = ival;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!convert_uc(args[1], &fillchar)) {
+        goto exit;
+    }
+skip_optional:
     return_value = unicode_rjust_impl(self, width, fillchar);
 
 exit:
@@ -833,10 +938,33 @@ unicode_maketrans(void *null, PyObject *const *args, Py_ssize_t nargs)
     PyObject *y = NULL;
     PyObject *z = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "O|UU:maketrans",
-        &x, &y, &z)) {
+    if (!_PyArg_CheckPositional("maketrans", nargs, 1, 3)) {
         goto exit;
     }
+    x = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!PyUnicode_Check(args[1])) {
+        _PyArg_BadArgument("maketrans", 2, "str", args[1]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[1]) == -1) {
+        goto exit;
+    }
+    y = args[1];
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (!PyUnicode_Check(args[2])) {
+        _PyArg_BadArgument("maketrans", 3, "str", args[2]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[2]) == -1) {
+        goto exit;
+    }
+    z = args[2];
+skip_optional:
     return_value = unicode_maketrans_impl(x, y, z);
 
 exit:
@@ -940,7 +1068,7 @@ unicode___format__(PyObject *self, PyObject *arg)
     PyObject *format_spec;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("__format__", "str", arg);
+        _PyArg_BadArgument("__format__", 0, "str", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg) == -1) {
@@ -970,4 +1098,4 @@ unicode_sizeof(PyObject *self, PyObject *Py_UNUSED(ignored))
 {
     return unicode_sizeof_impl(self);
 }
-/*[clinic end generated code: output=ff6acd5abd1998eb input=a9049054013a1b77]*/
+/*[clinic end generated code: output=73ad9670e00a2490 input=a9049054013a1b77]*/
diff --git a/Objects/stringlib/clinic/transmogrify.h.h b/Objects/stringlib/clinic/transmogrify.h.h
index 7b7fd58c7e7..15c43af61a2 100644
--- a/Objects/stringlib/clinic/transmogrify.h.h
+++ b/Objects/stringlib/clinic/transmogrify.h.h
@@ -55,10 +55,40 @@ stringlib_ljust(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
     Py_ssize_t width;
     char fillchar = ' ';
 
-    if (!_PyArg_ParseStack(args, nargs, "n|c:ljust",
-        &width, &fillchar)) {
+    if (!_PyArg_CheckPositional("ljust", nargs, 1, 2)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        width = ival;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyBytes_Check(args[1]) && PyBytes_GET_SIZE(args[1]) == 1) {
+        fillchar = PyBytes_AS_STRING(args[1])[0];
+    }
+    else if (PyByteArray_Check(args[1]) && PyByteArray_GET_SIZE(args[1]) == 1) {
+        fillchar = PyByteArray_AS_STRING(args[1])[0];
+    }
+    else {
+        _PyArg_BadArgument("ljust", 2, "a byte string of length 1", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = stringlib_ljust_impl(self, width, fillchar);
 
 exit:
@@ -86,10 +116,40 @@ stringlib_rjust(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
     Py_ssize_t width;
     char fillchar = ' ';
 
-    if (!_PyArg_ParseStack(args, nargs, "n|c:rjust",
-        &width, &fillchar)) {
+    if (!_PyArg_CheckPositional("rjust", nargs, 1, 2)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        width = ival;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyBytes_Check(args[1]) && PyBytes_GET_SIZE(args[1]) == 1) {
+        fillchar = PyBytes_AS_STRING(args[1])[0];
+    }
+    else if (PyByteArray_Check(args[1]) && PyByteArray_GET_SIZE(args[1]) == 1) {
+        fillchar = PyByteArray_AS_STRING(args[1])[0];
+    }
+    else {
+        _PyArg_BadArgument("rjust", 2, "a byte string of length 1", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = stringlib_rjust_impl(self, width, fillchar);
 
 exit:
@@ -117,10 +177,40 @@ stringlib_center(PyObject *self, PyObject *const *args, Py_ssize_t nargs)
     Py_ssize_t width;
     char fillchar = ' ';
 
-    if (!_PyArg_ParseStack(args, nargs, "n|c:center",
-        &width, &fillchar)) {
+    if (!_PyArg_CheckPositional("center", nargs, 1, 2)) {
         goto exit;
     }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    {
+        Py_ssize_t ival = -1;
+        PyObject *iobj = PyNumber_Index(args[0]);
+        if (iobj != NULL) {
+            ival = PyLong_AsSsize_t(iobj);
+            Py_DECREF(iobj);
+        }
+        if (ival == -1 && PyErr_Occurred()) {
+            goto exit;
+        }
+        width = ival;
+    }
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyBytes_Check(args[1]) && PyBytes_GET_SIZE(args[1]) == 1) {
+        fillchar = PyBytes_AS_STRING(args[1])[0];
+    }
+    else if (PyByteArray_Check(args[1]) && PyByteArray_GET_SIZE(args[1]) == 1) {
+        fillchar = PyByteArray_AS_STRING(args[1])[0];
+    }
+    else {
+        _PyArg_BadArgument("center", 2, "a byte string of length 1", args[1]);
+        goto exit;
+    }
+skip_optional:
     return_value = stringlib_center_impl(self, width, fillchar);
 
 exit:
@@ -169,4 +259,4 @@ stringlib_zfill(PyObject *self, PyObject *arg)
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=bf2ef501639e1190 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=787248a980f6a00e input=a9049054013a1b77]*/
diff --git a/PC/clinic/msvcrtmodule.c.h b/PC/clinic/msvcrtmodule.c.h
index b1c588b0642..d8e77d5f328 100644
--- a/PC/clinic/msvcrtmodule.c.h
+++ b/PC/clinic/msvcrtmodule.c.h
@@ -50,8 +50,34 @@ msvcrt_locking(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int mode;
     long nbytes;
 
-    if (!_PyArg_ParseStack(args, nargs, "iil:locking",
-        &fd, &mode, &nbytes)) {
+    if (!_PyArg_CheckPositional("locking", nargs, 3, 3)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd = _PyLong_AsInt(args[0]);
+    if (fd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    mode = _PyLong_AsInt(args[1]);
+    if (mode == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    nbytes = PyLong_AsLong(args[2]);
+    if (nbytes == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = msvcrt_locking_impl(module, fd, mode, nbytes);
@@ -85,8 +111,25 @@ msvcrt_setmode(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     int flags;
     long _return_value;
 
-    if (!_PyArg_ParseStack(args, nargs, "ii:setmode",
-        &fd, &flags)) {
+    if (!_PyArg_CheckPositional("setmode", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    fd = _PyLong_AsInt(args[0]);
+    if (fd == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    flags = _PyLong_AsInt(args[1]);
+    if (flags == -1 && PyErr_Occurred()) {
         goto exit;
     }
     _return_value = msvcrt_setmode_impl(module, fd, flags);
@@ -332,7 +375,7 @@ msvcrt_putch(PyObject *module, PyObject *arg)
         char_value = PyByteArray_AS_STRING(arg)[0];
     }
     else {
-        _PyArg_BadArgument("putch", "a byte string of length 1", arg);
+        _PyArg_BadArgument("putch", 0, "a byte string of length 1", arg);
         goto exit;
     }
     return_value = msvcrt_putch_impl(module, char_value);
@@ -360,14 +403,14 @@ msvcrt_putwch(PyObject *module, PyObject *arg)
     int unicode_char;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("putwch", "a unicode character", arg);
+        _PyArg_BadArgument("putwch", 0, "a unicode character", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg)) {
         goto exit;
     }
     if (PyUnicode_GET_LENGTH(arg) != 1) {
-        _PyArg_BadArgument("putwch", "a unicode character", arg);
+        _PyArg_BadArgument("putwch", 0, "a unicode character", arg);
         goto exit;
     }
     unicode_char = PyUnicode_READ_CHAR(arg, 0);
@@ -406,7 +449,7 @@ msvcrt_ungetch(PyObject *module, PyObject *arg)
         char_value = PyByteArray_AS_STRING(arg)[0];
     }
     else {
-        _PyArg_BadArgument("ungetch", "a byte string of length 1", arg);
+        _PyArg_BadArgument("ungetch", 0, "a byte string of length 1", arg);
         goto exit;
     }
     return_value = msvcrt_ungetch_impl(module, char_value);
@@ -434,14 +477,14 @@ msvcrt_ungetwch(PyObject *module, PyObject *arg)
     int unicode_char;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("ungetwch", "a unicode character", arg);
+        _PyArg_BadArgument("ungetwch", 0, "a unicode character", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg)) {
         goto exit;
     }
     if (PyUnicode_GET_LENGTH(arg) != 1) {
-        _PyArg_BadArgument("ungetwch", "a unicode character", arg);
+        _PyArg_BadArgument("ungetwch", 0, "a unicode character", arg);
         goto exit;
     }
     unicode_char = PyUnicode_READ_CHAR(arg, 0);
@@ -515,8 +558,25 @@ msvcrt_CrtSetReportMode(PyObject *module, PyObject *const *args, Py_ssize_t narg
     int mode;
     long _return_value;
 
-    if (!_PyArg_ParseStack(args, nargs, "ii:CrtSetReportMode",
-        &type, &mode)) {
+    if (!_PyArg_CheckPositional("CrtSetReportMode", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    type = _PyLong_AsInt(args[0]);
+    if (type == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    mode = _PyLong_AsInt(args[1]);
+    if (mode == -1 && PyErr_Occurred()) {
         goto exit;
     }
     _return_value = msvcrt_CrtSetReportMode_impl(module, type, mode);
@@ -619,4 +679,4 @@ exit:
 #ifndef MSVCRT_SET_ERROR_MODE_METHODDEF
     #define MSVCRT_SET_ERROR_MODE_METHODDEF
 #endif /* !defined(MSVCRT_SET_ERROR_MODE_METHODDEF) */
-/*[clinic end generated code: output=2530b4ff248563b4 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=816bc4f993893cea input=a9049054013a1b77]*/
diff --git a/PC/clinic/winreg.c.h b/PC/clinic/winreg.c.h
index 3b100f9bf08..21a9302d0af 100644
--- a/PC/clinic/winreg.c.h
+++ b/PC/clinic/winreg.c.h
@@ -425,8 +425,19 @@ winreg_EnumKey(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     HKEY key;
     int index;
 
-    if (!_PyArg_ParseStack(args, nargs, "O&i:EnumKey",
-        clinic_HKEY_converter, &key, &index)) {
+    if (!_PyArg_CheckPositional("EnumKey", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (!clinic_HKEY_converter(args[0], &key)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    index = _PyLong_AsInt(args[1]);
+    if (index == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = winreg_EnumKey_impl(module, key, index);
@@ -472,8 +483,19 @@ winreg_EnumValue(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     HKEY key;
     int index;
 
-    if (!_PyArg_ParseStack(args, nargs, "O&i:EnumValue",
-        clinic_HKEY_converter, &key, &index)) {
+    if (!_PyArg_CheckPositional("EnumValue", nargs, 2, 2)) {
+        goto exit;
+    }
+    if (!clinic_HKEY_converter(args[0], &key)) {
+        goto exit;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    index = _PyLong_AsInt(args[1]);
+    if (index == -1 && PyErr_Occurred()) {
         goto exit;
     }
     return_value = winreg_EnumValue_impl(module, key, index);
@@ -1095,4 +1117,4 @@ winreg_QueryReflectionKey(PyObject *module, PyObject *arg)
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=82bd56c524c6c3dd input=a9049054013a1b77]*/
+/*[clinic end generated code: output=bd491131d343ae7a input=a9049054013a1b77]*/
diff --git a/Python/clinic/bltinmodule.c.h b/Python/clinic/bltinmodule.c.h
index 7f043dac4f3..68d8dccea65 100644
--- a/Python/clinic/bltinmodule.c.h
+++ b/Python/clinic/bltinmodule.c.h
@@ -94,10 +94,22 @@ builtin_format(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *value;
     PyObject *format_spec = NULL;
 
-    if (!_PyArg_ParseStack(args, nargs, "O|U:format",
-        &value, &format_spec)) {
+    if (!_PyArg_CheckPositional("format", nargs, 1, 2)) {
         goto exit;
     }
+    value = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (!PyUnicode_Check(args[1])) {
+        _PyArg_BadArgument("format", 2, "str", args[1]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[1]) == -1) {
+        goto exit;
+    }
+    format_spec = args[1];
+skip_optional:
     return_value = builtin_format_impl(module, value, format_spec);
 
 exit:
@@ -717,4 +729,4 @@ builtin_issubclass(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
 exit:
     return return_value;
 }
-/*[clinic end generated code: output=ed300ebf3f6db530 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=11b5cd918bd7eb18 input=a9049054013a1b77]*/
diff --git a/Python/clinic/import.c.h b/Python/clinic/import.c.h
index d34d68fed55..783ed4ebb96 100644
--- a/Python/clinic/import.c.h
+++ b/Python/clinic/import.c.h
@@ -88,10 +88,22 @@ _imp__fix_co_filename(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyCodeObject *code;
     PyObject *path;
 
-    if (!_PyArg_ParseStack(args, nargs, "O!U:_fix_co_filename",
-        &PyCode_Type, &code, &path)) {
+    if (!_PyArg_CheckPositional("_fix_co_filename", nargs, 2, 2)) {
         goto exit;
     }
+    if (!PyObject_TypeCheck(args[0], &PyCode_Type)) {
+        _PyArg_BadArgument("_fix_co_filename", 1, (&PyCode_Type)->tp_name, args[0]);
+        goto exit;
+    }
+    code = (PyCodeObject *)args[0];
+    if (!PyUnicode_Check(args[1])) {
+        _PyArg_BadArgument("_fix_co_filename", 2, "str", args[1]);
+        goto exit;
+    }
+    if (PyUnicode_READY(args[1]) == -1) {
+        goto exit;
+    }
+    path = args[1];
     return_value = _imp__fix_co_filename_impl(module, code, path);
 
 exit:
@@ -144,7 +156,7 @@ _imp_init_frozen(PyObject *module, PyObject *arg)
     PyObject *name;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("init_frozen", "str", arg);
+        _PyArg_BadArgument("init_frozen", 0, "str", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg) == -1) {
@@ -176,7 +188,7 @@ _imp_get_frozen_object(PyObject *module, PyObject *arg)
     PyObject *name;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("get_frozen_object", "str", arg);
+        _PyArg_BadArgument("get_frozen_object", 0, "str", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg) == -1) {
@@ -208,7 +220,7 @@ _imp_is_frozen_package(PyObject *module, PyObject *arg)
     PyObject *name;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("is_frozen_package", "str", arg);
+        _PyArg_BadArgument("is_frozen_package", 0, "str", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg) == -1) {
@@ -240,7 +252,7 @@ _imp_is_builtin(PyObject *module, PyObject *arg)
     PyObject *name;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("is_builtin", "str", arg);
+        _PyArg_BadArgument("is_builtin", 0, "str", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg) == -1) {
@@ -272,7 +284,7 @@ _imp_is_frozen(PyObject *module, PyObject *arg)
     PyObject *name;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("is_frozen", "str", arg);
+        _PyArg_BadArgument("is_frozen", 0, "str", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg) == -1) {
@@ -421,4 +433,4 @@ exit:
 #ifndef _IMP_EXEC_DYNAMIC_METHODDEF
     #define _IMP_EXEC_DYNAMIC_METHODDEF
 #endif /* !defined(_IMP_EXEC_DYNAMIC_METHODDEF) */
-/*[clinic end generated code: output=d8be58c9541122f1 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=22062cee6e8ba7f3 input=a9049054013a1b77]*/
diff --git a/Python/clinic/marshal.c.h b/Python/clinic/marshal.c.h
index 516a31582cc..ab4575340e2 100644
--- a/Python/clinic/marshal.c.h
+++ b/Python/clinic/marshal.c.h
@@ -34,10 +34,24 @@ marshal_dump(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *file;
     int version = Py_MARSHAL_VERSION;
 
-    if (!_PyArg_ParseStack(args, nargs, "OO|i:dump",
-        &value, &file, &version)) {
+    if (!_PyArg_CheckPositional("dump", nargs, 2, 3)) {
         goto exit;
     }
+    value = args[0];
+    file = args[1];
+    if (nargs < 3) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[2])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    version = _PyLong_AsInt(args[2]);
+    if (version == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = marshal_dump_impl(module, value, file, version);
 
 exit:
@@ -90,10 +104,23 @@ marshal_dumps(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *value;
     int version = Py_MARSHAL_VERSION;
 
-    if (!_PyArg_ParseStack(args, nargs, "O|i:dumps",
-        &value, &version)) {
+    if (!_PyArg_CheckPositional("dumps", nargs, 1, 2)) {
         goto exit;
     }
+    value = args[0];
+    if (nargs < 2) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[1])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    version = _PyLong_AsInt(args[1]);
+    if (version == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = marshal_dumps_impl(module, value, version);
 
 exit:
@@ -125,7 +152,7 @@ marshal_loads(PyObject *module, PyObject *arg)
         goto exit;
     }
     if (!PyBuffer_IsContiguous(&bytes, 'C')) {
-        _PyArg_BadArgument("loads", "contiguous buffer", arg);
+        _PyArg_BadArgument("loads", 0, "contiguous buffer", arg);
         goto exit;
     }
     return_value = marshal_loads_impl(module, &bytes);
@@ -138,4 +165,4 @@ exit:
 
     return return_value;
 }
-/*[clinic end generated code: output=8262e7e6c8cbc1ef input=a9049054013a1b77]*/
+/*[clinic end generated code: output=ae2bca1aa239e095 input=a9049054013a1b77]*/
diff --git a/Python/clinic/sysmodule.c.h b/Python/clinic/sysmodule.c.h
index 2d9c6e2beee..7370ab59ac0 100644
--- a/Python/clinic/sysmodule.c.h
+++ b/Python/clinic/sysmodule.c.h
@@ -175,7 +175,7 @@ sys_intern(PyObject *module, PyObject *arg)
     PyObject *s;
 
     if (!PyUnicode_Check(arg)) {
-        _PyArg_BadArgument("intern", "str", arg);
+        _PyArg_BadArgument("intern", 0, "str", arg);
         goto exit;
     }
     if (PyUnicode_READY(arg) == -1) {
@@ -819,10 +819,22 @@ sys__getframe(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *return_value = NULL;
     int depth = 0;
 
-    if (!_PyArg_ParseStack(args, nargs, "|i:_getframe",
-        &depth)) {
+    if (!_PyArg_CheckPositional("_getframe", nargs, 0, 1)) {
         goto exit;
     }
+    if (nargs < 1) {
+        goto skip_optional;
+    }
+    if (PyFloat_Check(args[0])) {
+        PyErr_SetString(PyExc_TypeError,
+                        "integer argument expected, got float" );
+        goto exit;
+    }
+    depth = _PyLong_AsInt(args[0]);
+    if (depth == -1 && PyErr_Occurred()) {
+        goto exit;
+    }
+skip_optional:
     return_value = sys__getframe_impl(module, depth);
 
 exit:
@@ -872,10 +884,15 @@ sys_call_tracing(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
     PyObject *func;
     PyObject *funcargs;
 
-    if (!_PyArg_ParseStack(args, nargs, "OO!:call_tracing",
-        &func, &PyTuple_Type, &funcargs)) {
+    if (!_PyArg_CheckPositional("call_tracing", nargs, 2, 2)) {
         goto exit;
     }
+    func = args[0];
+    if (!PyTuple_Check(args[1])) {
+        _PyArg_BadArgument("call_tracing", 2, "tuple", args[1]);
+        goto exit;
+    }
+    funcargs = args[1];
     return_value = sys_call_tracing_impl(module, func, funcargs);
 
 exit:
@@ -1029,4 +1046,4 @@ sys_getandroidapilevel(PyObject *module, PyObject *Py_UNUSED(ignored))
 #ifndef SYS_GETANDROIDAPILEVEL_METHODDEF
     #define SYS_GETANDROIDAPILEVEL_METHODDEF
 #endif /* !defined(SYS_GETANDROIDAPILEVEL_METHODDEF) */
-/*[clinic end generated code: output=0e662f2e19293d57 input=a9049054013a1b77]*/
+/*[clinic end generated code: output=6a5202e5bfe5e6bd input=a9049054013a1b77]*/
diff --git a/Python/getargs.c b/Python/getargs.c
index 550d0df6950..c491169abe5 100644
--- a/Python/getargs.c
+++ b/Python/getargs.c
@@ -613,11 +613,21 @@ convertitem(PyObject *arg, const char **p_format, va_list *p_va, int flags,
 /* Format an error message generated by convertsimple(). */
 
 void
-_PyArg_BadArgument(const char *fname, const char *expected, PyObject *arg)
+_PyArg_BadArgument(const char *fname, int iarg,
+                   const char *expected, PyObject *arg)
 {
-    PyErr_Format(PyExc_TypeError, "%.200s() argument must be %.50s, not %.50s",
-                 fname, expected,
-                 arg == Py_None ? "None" : arg->ob_type->tp_name);
+    if (iarg) {
+        PyErr_Format(PyExc_TypeError,
+                     "%.200s() argument %d must be %.50s, not %.50s",
+                     fname, iarg, expected,
+                     arg == Py_None ? "None" : arg->ob_type->tp_name);
+    }
+    else {
+        PyErr_Format(PyExc_TypeError,
+                     "%.200s() argument must be %.50s, not %.50s",
+                     fname, expected,
+                     arg == Py_None ? "None" : arg->ob_type->tp_name);
+    }
 }
 
 static const char *
@@ -2416,13 +2426,12 @@ skipitem(const char **p_format, va_list *p_va, int flags)
 }
 
 
-static int
-unpack_stack(PyObject *const *args, Py_ssize_t nargs, const char *name,
-             Py_ssize_t min, Py_ssize_t max, va_list vargs)
-{
-    Py_ssize_t i;
-    PyObject **o;
+#undef _PyArg_CheckPositional
 
+int
+_PyArg_CheckPositional(const char *name, Py_ssize_t nargs,
+                       Py_ssize_t min, Py_ssize_t max)
+{
     assert(min >= 0);
     assert(min <= max);
 
@@ -2460,6 +2469,20 @@ unpack_stack(PyObject *const *args, Py_ssize_t nargs, const char *name,
         return 0;
     }
 
+    return 1;
+}
+
+static int
+unpack_stack(PyObject *const *args, Py_ssize_t nargs, const char *name,
+             Py_ssize_t min, Py_ssize_t max, va_list vargs)
+{
+    Py_ssize_t i;
+    PyObject **o;
+
+    if (!_PyArg_CheckPositional(name, nargs, min, max)) {
+        return 0;
+    }
+
     for (i = 0; i < nargs; i++) {
         o = va_arg(vargs, PyObject **);
         *o = args[i];
diff --git a/Tools/clinic/clinic.py b/Tools/clinic/clinic.py
index 3627725eece..4087d3fec93 100755
--- a/Tools/clinic/clinic.py
+++ b/Tools/clinic/clinic.py
@@ -807,8 +807,13 @@ def insert_keywords(s):
                     {c_basename}({self_type}{self_name}, PyObject *%s)
                     """ % argname)
 
-                parsearg = converters[0].parse_arg(argname)
-                assert parsearg is not None
+                parsearg = converters[0].parse_arg(argname, 0)
+                if parsearg is None:
+                    parsearg = """
+                        if (!PyArg_Parse(%s, "{format_units}:{name}", {parse_arguments})) {{
+                            goto exit;
+                        }}
+                        """ % argname
                 parser_definition = parser_body(parser_prototype,
                                                 normalize_snippet(parsearg, indent=4))
 
@@ -857,26 +862,58 @@ def insert_keywords(s):
 
                 flags = "METH_FASTCALL"
                 parser_prototype = parser_prototype_fastcall
-
-                parser_definition = parser_body(parser_prototype, normalize_snippet("""
-                    if (!_PyArg_ParseStack(args, nargs, "{format_units}:{name}",
-                        {parse_arguments})) {{
-                        goto exit;
-                    }}
-                    """, indent=4))
+                nargs = 'nargs'
+                argname_fmt = 'args[%d]'
             else:
                 # positional-only, but no option groups
                 # we only need one call to PyArg_ParseTuple
 
                 flags = "METH_VARARGS"
                 parser_prototype = parser_prototype_varargs
+                nargs = 'PyTuple_GET_SIZE(args)'
+                argname_fmt = 'PyTuple_GET_ITEM(args, %d)'
 
-                parser_definition = parser_body(parser_prototype, normalize_snippet("""
-                    if (!PyArg_ParseTuple(args, "{format_units}:{name}",
-                        {parse_arguments})) {{
+            parser_code = []
+            has_optional = False
+            for i, converter in enumerate(converters):
+                parsearg = converter.parse_arg(argname_fmt % i, i + 1)
+                if parsearg is None:
+                    #print('Cannot convert %s %r for %s' % (converter.__class__.__name__, converter.format_unit, converter.name), file=sys.stderr)
+                    parser_code = None
+                    break
+                if has_optional or converter.default is not unspecified:
+                    has_optional = True
+                    parser_code.append(normalize_snippet("""
+                        if (%s < %d) {{
+                            goto skip_optional;
+                        }}
+                        """, indent=4) % (nargs, i + 1))
+                parser_code.append(normalize_snippet(parsearg, indent=4))
+
+            if parser_code is not None:
+                parser_code.insert(0, normalize_snippet("""
+                    if (!_PyArg_CheckPositional("{name}", %s, {unpack_min}, {unpack_max})) {{
                         goto exit;
                     }}
-                    """, indent=4))
+                    """ % nargs, indent=4))
+                if has_optional:
+                    parser_code.append("skip_optional:")
+            else:
+                if not new_or_init:
+                    parser_code = [normalize_snippet("""
+                        if (!_PyArg_ParseStack(args, nargs, "{format_units}:{name}",
+                            {parse_arguments})) {{
+                            goto exit;
+                        }}
+                        """, indent=4)]
+                else:
+                    parser_code = [normalize_snippet("""
+                        if (!PyArg_ParseTuple(args, "{format_units}:{name}",
+                            {parse_arguments})) {{
+                            goto exit;
+                        }}
+                        """, indent=4)]
+            parser_definition = parser_body(parser_prototype, *parser_code)
 
         elif not new_or_init:
             flags = "METH_FASTCALL|METH_KEYWORDS"
@@ -2536,7 +2573,7 @@ def pre_render(self):
         """
         pass
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'O&':
             return """
                 if (!{converter}({argname}, &{paramname})) {{{{
@@ -2550,25 +2587,27 @@ def parse_arg(self, argname):
                 typecheck, typename = type_checks[self.subclass_of]
                 return """
                     if (!{typecheck}({argname})) {{{{
-                        _PyArg_BadArgument("{{name}}", "{typename}", {argname});
+                        _PyArg_BadArgument("{{name}}", {argnum}, "{typename}", {argname});
                         goto exit;
                     }}}}
                     {paramname} = {cast}{argname};
                     """.format(argname=argname, paramname=self.name,
+                               argnum=argnum,
                                typecheck=typecheck, typename=typename, cast=cast)
             return """
                 if (!PyObject_TypeCheck({argname}, {subclass_of})) {{{{
-                    _PyArg_BadArgument("{{name}}", ({subclass_of})->tp_name, {argname});
+                    _PyArg_BadArgument("{{name}}", {argnum}, ({subclass_of})->tp_name, {argname});
                     goto exit;
                 }}}}
                 {paramname} = {cast}{argname};
-                """.format(argname=argname, paramname=self.name,
+                """.format(argname=argname, paramname=self.name, argnum=argnum,
                            subclass_of=self.subclass_of, cast=cast)
-        return """
-            if (!PyArg_Parse(%s, "{format_units}:{name}", {parse_arguments})) {{
-                goto exit;
-            }}
-            """ % argname
+        if self.format_unit == 'O':
+            cast = '(%s)' % self.type if self.type != 'PyObject *' else ''
+            return """
+                {paramname} = {cast}{argname};
+                """.format(argname=argname, paramname=self.name, cast=cast)
+        return None
 
 type_checks = {
     '&PyLong_Type': ('PyLong_Check', 'int'),
@@ -2598,7 +2637,7 @@ def converter_init(self, *, accept={object}):
             self.default = bool(self.default)
             self.c_default = str(int(self.default))
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'i':
             return """
                 if (PyFloat_Check({argname})) {{{{
@@ -2618,7 +2657,7 @@ def parse_arg(self, argname):
                     goto exit;
                 }}}}
                 """.format(argname=argname, paramname=self.name)
-        return super().parse_arg(argname)
+        return super().parse_arg(argname, argnum)
 
 class char_converter(CConverter):
     type = 'char'
@@ -2635,7 +2674,7 @@ def converter_init(self):
             if self.c_default == '"\'"':
                 self.c_default = r"'\''"
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'c':
             return """
                 if (PyBytes_Check({argname}) && PyBytes_GET_SIZE({argname}) == 1) {{{{
@@ -2645,11 +2684,11 @@ def parse_arg(self, argname):
                     {paramname} = PyByteArray_AS_STRING({argname})[0];
                 }}}}
                 else {{{{
-                    _PyArg_BadArgument("{{name}}", "a byte string of length 1", {argname});
+                    _PyArg_BadArgument("{{name}}", {argnum}, "a byte string of length 1", {argname});
                     goto exit;
                 }}}}
-                """.format(argname=argname, paramname=self.name)
-        return super().parse_arg(argname)
+                """.format(argname=argname, paramname=self.name, argnum=argnum)
+        return super().parse_arg(argname, argnum)
 
 
 @add_legacy_c_converter('B', bitwise=True)
@@ -2663,7 +2702,7 @@ def converter_init(self, *, bitwise=False):
         if bitwise:
             self.format_unit = 'B'
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'b':
             return """
                 if (PyFloat_Check({argname})) {{{{
@@ -2708,7 +2747,7 @@ def parse_arg(self, argname):
                     }}}}
                 }}}}
                 """.format(argname=argname, paramname=self.name)
-        return super().parse_arg(argname)
+        return super().parse_arg(argname, argnum)
 
 class byte_converter(unsigned_char_converter): pass
 
@@ -2718,7 +2757,7 @@ class short_converter(CConverter):
     format_unit = 'h'
     c_ignored_default = "0"
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'h':
             return """
                 if (PyFloat_Check({argname})) {{{{
@@ -2746,7 +2785,7 @@ def parse_arg(self, argname):
                     }}}}
                 }}}}
                 """.format(argname=argname, paramname=self.name)
-        return super().parse_arg(argname)
+        return super().parse_arg(argname, argnum)
 
 class unsigned_short_converter(CConverter):
     type = 'unsigned short'
@@ -2759,6 +2798,21 @@ def converter_init(self, *, bitwise=False):
         else:
             self.converter = '_PyLong_UnsignedShort_Converter'
 
+    def parse_arg(self, argname, argnum):
+        if self.format_unit == 'H':
+            return """
+                if (PyFloat_Check({argname})) {{{{
+                    PyErr_SetString(PyExc_TypeError,
+                                    "integer argument expected, got float" );
+                    goto exit;
+                }}}}
+                {paramname} = (unsigned short)PyLong_AsUnsignedLongMask({argname});
+                if ({paramname} == (unsigned short)-1 && PyErr_Occurred()) {{{{
+                    goto exit;
+                }}}}
+                """.format(argname=argname, paramname=self.name)
+        return super().parse_arg(argname, argnum)
+
 @add_legacy_c_converter('C', accept={str})
 class int_converter(CConverter):
     type = 'int'
@@ -2774,7 +2828,7 @@ def converter_init(self, *, accept={int}, type=None):
         if type != None:
             self.type = type
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'i':
             return """
                 if (PyFloat_Check({argname})) {{{{
@@ -2790,19 +2844,19 @@ def parse_arg(self, argname):
         elif self.format_unit == 'C':
             return """
                 if (!PyUnicode_Check({argname})) {{{{
-                    _PyArg_BadArgument("{{name}}", "a unicode character", {argname});
+                    _PyArg_BadArgument("{{name}}", {argnum}, "a unicode character", {argname});
                     goto exit;
                 }}}}
                 if (PyUnicode_READY({argname})) {{{{
                     goto exit;
                 }}}}
                 if (PyUnicode_GET_LENGTH({argname}) != 1) {{{{
-                    _PyArg_BadArgument("{{name}}", "a unicode character", {argname});
+                    _PyArg_BadArgument("{{name}}", {argnum}, "a unicode character", {argname});
                     goto exit;
                 }}}}
                 {paramname} = PyUnicode_READ_CHAR({argname}, 0);
-                """.format(argname=argname, paramname=self.name)
-        return super().parse_arg(argname)
+                """.format(argname=argname, paramname=self.name, argnum=argnum)
+        return super().parse_arg(argname, argnum)
 
 class unsigned_int_converter(CConverter):
     type = 'unsigned int'
@@ -2815,7 +2869,7 @@ def converter_init(self, *, bitwise=False):
         else:
             self.converter = '_PyLong_UnsignedInt_Converter'
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'I':
             return """
                 if (PyFloat_Check({argname})) {{{{
@@ -2828,7 +2882,7 @@ def parse_arg(self, argname):
                     goto exit;
                 }}}}
                 """.format(argname=argname, paramname=self.name)
-        return super().parse_arg(argname)
+        return super().parse_arg(argname, argnum)
 
 class long_converter(CConverter):
     type = 'long'
@@ -2836,7 +2890,7 @@ class long_converter(CConverter):
     format_unit = 'l'
     c_ignored_default = "0"
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'l':
             return """
                 if (PyFloat_Check({argname})) {{{{
@@ -2849,7 +2903,7 @@ def parse_arg(self, argname):
                     goto exit;
                 }}}}
                 """.format(argname=argname, paramname=self.name)
-        return super().parse_arg(argname)
+        return super().parse_arg(argname, argnum)
 
 class unsigned_long_converter(CConverter):
     type = 'unsigned long'
@@ -2862,16 +2916,16 @@ def converter_init(self, *, bitwise=False):
         else:
             self.converter = '_PyLong_UnsignedLong_Converter'
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'k':
             return """
                 if (!PyLong_Check({argname})) {{{{
-                    _PyArg_BadArgument("{{name}}", "int", {argname});
+                    _PyArg_BadArgument("{{name}}", {argnum}, "int", {argname});
                     goto exit;
                 }}}}
                 {paramname} = PyLong_AsUnsignedLongMask({argname});
-                """.format(argname=argname, paramname=self.name)
-        return super().parse_arg(argname)
+                """.format(argname=argname, paramname=self.name, argnum=argnum)
+        return super().parse_arg(argname, argnum)
 
 class long_long_converter(CConverter):
     type = 'long long'
@@ -2879,7 +2933,7 @@ class long_long_converter(CConverter):
     format_unit = 'L'
     c_ignored_default = "0"
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'L':
             return """
                 if (PyFloat_Check({argname})) {{{{
@@ -2892,7 +2946,7 @@ def parse_arg(self, argname):
                     goto exit;
                 }}}}
                 """.format(argname=argname, paramname=self.name)
-        return super().parse_arg(argname)
+        return super().parse_arg(argname, argnum)
 
 class unsigned_long_long_converter(CConverter):
     type = 'unsigned long long'
@@ -2905,16 +2959,16 @@ def converter_init(self, *, bitwise=False):
         else:
             self.converter = '_PyLong_UnsignedLongLong_Converter'
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'K':
             return """
                 if (!PyLong_Check({argname})) {{{{
-                    _PyArg_BadArgument("{{name}}", "int", {argname});
+                    _PyArg_BadArgument("{{name}}", {argnum}, "int", {argname});
                     goto exit;
                 }}}}
                 {paramname} = PyLong_AsUnsignedLongLongMask({argname});
-                """.format(argname=argname, paramname=self.name)
-        return super().parse_arg(argname)
+                """.format(argname=argname, paramname=self.name, argnum=argnum)
+        return super().parse_arg(argname, argnum)
 
 class Py_ssize_t_converter(CConverter):
     type = 'Py_ssize_t'
@@ -2929,7 +2983,7 @@ def converter_init(self, *, accept={int}):
         else:
             fail("Py_ssize_t_converter: illegal 'accept' argument " + repr(accept))
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'n':
             return """
                 if (PyFloat_Check({argname})) {{{{
@@ -2950,7 +3004,7 @@ def parse_arg(self, argname):
                     {paramname} = ival;
                 }}}}
                 """.format(argname=argname, paramname=self.name)
-        return super().parse_arg(argname)
+        return super().parse_arg(argname, argnum)
 
 
 class slice_index_converter(CConverter):
@@ -2969,7 +3023,7 @@ class size_t_converter(CConverter):
     converter = '_PyLong_Size_t_Converter'
     c_ignored_default = "0"
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'n':
             return """
                 {paramname} = PyNumber_AsSsize_t({argname}, PyExc_OverflowError);
@@ -2977,7 +3031,7 @@ def parse_arg(self, argname):
                     goto exit;
                 }}}}
                 """.format(argname=argname, paramname=self.name)
-        return super().parse_arg(argname)
+        return super().parse_arg(argname, argnum)
 
 
 class float_converter(CConverter):
@@ -2986,7 +3040,7 @@ class float_converter(CConverter):
     format_unit = 'f'
     c_ignored_default = "0.0"
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'f':
             return """
                 {paramname} = (float) PyFloat_AsDouble({argname});
@@ -2994,7 +3048,7 @@ def parse_arg(self, argname):
                     goto exit;
                 }}}}
                 """.format(argname=argname, paramname=self.name)
-        return super().parse_arg(argname)
+        return super().parse_arg(argname, argnum)
 
 class double_converter(CConverter):
     type = 'double'
@@ -3002,7 +3056,7 @@ class double_converter(CConverter):
     format_unit = 'd'
     c_ignored_default = "0.0"
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'd':
             return """
                 {paramname} = PyFloat_AsDouble({argname});
@@ -3010,7 +3064,7 @@ def parse_arg(self, argname):
                     goto exit;
                 }}}}
                 """.format(argname=argname, paramname=self.name)
-        return super().parse_arg(argname)
+        return super().parse_arg(argname, argnum)
 
 
 class Py_complex_converter(CConverter):
@@ -3019,7 +3073,7 @@ class Py_complex_converter(CConverter):
     format_unit = 'D'
     c_ignored_default = "{0.0, 0.0}"
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'D':
             return """
                 {paramname} = PyComplex_AsCComplex({argname});
@@ -3027,7 +3081,7 @@ def parse_arg(self, argname):
                     goto exit;
                 }}}}
                 """.format(argname=argname, paramname=self.name)
-        return super().parse_arg(argname)
+        return super().parse_arg(argname, argnum)
 
 
 class object_converter(CConverter):
@@ -3093,11 +3147,11 @@ def cleanup(self):
             name = self.name
             return "".join(["if (", name, ") {\n   PyMem_FREE(", name, ");\n}\n"])
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 's':
             return """
                 if (!PyUnicode_Check({argname})) {{{{
-                    _PyArg_BadArgument("{{name}}", "str", {argname});
+                    _PyArg_BadArgument("{{name}}", {argnum}, "str", {argname});
                     goto exit;
                 }}}}
                 Py_ssize_t {paramname}_length;
@@ -3109,8 +3163,29 @@ def parse_arg(self, argname):
                     PyErr_SetString(PyExc_ValueError, "embedded null character");
                     goto exit;
                 }}}}
-                """.format(argname=argname, paramname=self.name)
-        return super().parse_arg(argname)
+                """.format(argname=argname, paramname=self.name, argnum=argnum)
+        if self.format_unit == 'z':
+            return """
+                if ({argname} == Py_None) {{{{
+                    {paramname} = NULL;
+                }}}}
+                else if (PyUnicode_Check({argname})) {{{{
+                    Py_ssize_t {paramname}_length;
+                    {paramname} = PyUnicode_AsUTF8AndSize({argname}, &{paramname}_length);
+                    if ({paramname} == NULL) {{{{
+                        goto exit;
+                    }}}}
+                    if (strlen({paramname}) != (size_t){paramname}_length) {{{{
+                        PyErr_SetString(PyExc_ValueError, "embedded null character");
+                        goto exit;
+                    }}}}
+                }}}}
+                else {{{{
+                    _PyArg_BadArgument("{{name}}", {argnum}, "str or None", {argname});
+                    goto exit;
+                }}}}
+                """.format(argname=argname, paramname=self.name, argnum=argnum)
+        return super().parse_arg(argname, argnum)
 
 #
 # This is the fourth or fifth rewrite of registering all the
@@ -3165,51 +3240,53 @@ class PyBytesObject_converter(CConverter):
     format_unit = 'S'
     # accept = {bytes}
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'S':
             return """
                 if (!PyBytes_Check({argname})) {{{{
-                    _PyArg_BadArgument("{{name}}", "bytes", {argname});
+                    _PyArg_BadArgument("{{name}}", {argnum}, "bytes", {argname});
                     goto exit;
                 }}}}
                 {paramname} = ({type}){argname};
-                """.format(argname=argname, paramname=self.name, type=self.type)
-        return super().parse_arg(argname)
+                """.format(argname=argname, paramname=self.name, argnum=argnum,
+                           type=self.type)
+        return super().parse_arg(argname, argnum)
 
 class PyByteArrayObject_converter(CConverter):
     type = 'PyByteArrayObject *'
     format_unit = 'Y'
     # accept = {bytearray}
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'Y':
             return """
                 if (!PyByteArray_Check({argname})) {{{{
-                    _PyArg_BadArgument("{{name}}", "bytearray", {argname});
+                    _PyArg_BadArgument("{{name}}", {argnum}, "bytearray", {argname});
                     goto exit;
                 }}}}
                 {paramname} = ({type}){argname};
-                """.format(argname=argname, paramname=self.name, type=self.type)
-        return super().parse_arg(argname)
+                """.format(argname=argname, paramname=self.name, argnum=argnum,
+                           type=self.type)
+        return super().parse_arg(argname, argnum)
 
 class unicode_converter(CConverter):
     type = 'PyObject *'
     default_type = (str, Null, NoneType)
     format_unit = 'U'
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'U':
             return """
                 if (!PyUnicode_Check({argname})) {{{{
-                    _PyArg_BadArgument("{{name}}", "str", {argname});
+                    _PyArg_BadArgument("{{name}}", {argnum}, "str", {argname});
                     goto exit;
                 }}}}
                 if (PyUnicode_READY({argname}) == -1) {{{{
                     goto exit;
                 }}}}
                 {paramname} = {argname};
-                """.format(argname=argname, paramname=self.name)
-        return super().parse_arg(argname)
+                """.format(argname=argname, paramname=self.name, argnum=argnum)
+        return super().parse_arg(argname, argnum)
 
 @add_legacy_c_converter('u#', zeroes=True)
 @add_legacy_c_converter('Z', accept={str, NoneType})
@@ -3258,17 +3335,17 @@ def cleanup(self):
         name = self.name
         return "".join(["if (", name, ".obj) {\n   PyBuffer_Release(&", name, ");\n}\n"])
 
-    def parse_arg(self, argname):
+    def parse_arg(self, argname, argnum):
         if self.format_unit == 'y*':
             return """
                 if (PyObject_GetBuffer({argname}, &{paramname}, PyBUF_SIMPLE) != 0) {{{{
                     goto exit;
                 }}}}
                 if (!PyBuffer_IsContiguous(&{paramname}, 'C')) {{{{
-                    _PyArg_BadArgument("{{name}}", "contiguous buffer", {argname});
+                    _PyArg_BadArgument("{{name}}", {argnum}, "contiguous buffer", {argname});
                     goto exit;
                 }}}}
-                """.format(argname=argname, paramname=self.name)
+                """.format(argname=argname, paramname=self.name, argnum=argnum)
         elif self.format_unit == 's*':
             return """
                 if (PyUnicode_Check({argname})) {{{{
@@ -3284,24 +3361,24 @@ def parse_arg(self, argname):
                         goto exit;
                     }}}}
                     if (!PyBuffer_IsContiguous(&{paramname}, 'C')) {{{{
-                        _PyArg_BadArgument("{{name}}", "contiguous buffer", {argname});
+                        _PyArg_BadArgument("{{name}}", {argnum}, "contiguous buffer", {argname});
                         goto exit;
                     }}}}
                 }}}}
-                """.format(argname=argname, paramname=self.name)
+                """.format(argname=argname, paramname=self.name, argnum=argnum)
         elif self.format_unit == 'w*':
             return """
                 if (PyObject_GetBuffer({argname}, &{paramname}, PyBUF_WRITABLE) < 0) {{{{
                     PyErr_Clear();
-                    _PyArg_BadArgument("{{name}}", "read-write bytes-like object", {argname});
+                    _PyArg_BadArgument("{{name}}", {argnum}, "read-write bytes-like object", {argname});
                     goto exit;
                 }}}}
                 if (!PyBuffer_IsContiguous(&{paramname}, 'C')) {{{{
-                    _PyArg_BadArgument("{{name}}", "contiguous buffer", {argname});
+                    _PyArg_BadArgument("{{name}}", {argnum}, "contiguous buffer", {argname});
                     goto exit;
                 }}}}
-                """.format(argname=argname, paramname=self.name)
-        return super().parse_arg(argname)
+                """.format(argname=argname, paramname=self.name, argnum=argnum)
+        return super().parse_arg(argname, argnum)
 
 
 def correct_name_for_self(f):