diff --git a/Include/cpython/frameobject.h b/Include/cpython/frameobject.h
index e69209686be..ebaecbed1b4 100644
--- a/Include/cpython/frameobject.h
+++ b/Include/cpython/frameobject.h
@@ -13,11 +13,6 @@ PyAPI_DATA(PyTypeObject) PyFrame_Type;
 PyAPI_FUNC(PyFrameObject *) PyFrame_New(PyThreadState *, PyCodeObject *,
                                         PyObject *, PyObject *);
 
-/* only internal use */
-PyFrameObject*
-_PyFrame_New_NoTrack(PyCodeObject *code);
-
-
 /* The rest of the interface is specific for frame objects */
 
 /* Conversions between "fast locals" and locals in dictionary */
diff --git a/Include/cpython/funcobject.h b/Include/cpython/funcobject.h
index 9f0560fb725..99ac6008f8b 100644
--- a/Include/cpython/funcobject.h
+++ b/Include/cpython/funcobject.h
@@ -82,8 +82,6 @@ PyAPI_FUNC(PyObject *) _PyFunction_Vectorcall(
     size_t nargsf,
     PyObject *kwnames);
 
-uint32_t _PyFunction_GetVersionForCurrentState(PyFunctionObject *func);
-
 /* Macros for direct access to these values. Type checks are *not*
    done, so use with care. */
 #define PyFunction_GET_CODE(func) \
diff --git a/Include/cpython/genobject.h b/Include/cpython/genobject.h
index 838ca6cd246..b485ac6183e 100644
--- a/Include/cpython/genobject.h
+++ b/Include/cpython/genobject.h
@@ -45,7 +45,6 @@ PyAPI_FUNC(PyObject *) PyGen_NewWithQualName(PyFrameObject *,
     PyObject *name, PyObject *qualname);
 PyAPI_FUNC(int) _PyGen_SetStopIterationValue(PyObject *);
 PyAPI_FUNC(int) _PyGen_FetchStopIterationValue(PyObject **);
-PyObject *_PyGen_yf(PyGenObject *);
 PyAPI_FUNC(void) _PyGen_Finalize(PyObject *self);
 
 
@@ -59,7 +58,6 @@ PyAPI_DATA(PyTypeObject) PyCoro_Type;
 PyAPI_DATA(PyTypeObject) _PyCoroWrapper_Type;
 
 #define PyCoro_CheckExact(op) Py_IS_TYPE(op, &PyCoro_Type)
-PyObject *_PyCoro_GetAwaitableIter(PyObject *o);
 PyAPI_FUNC(PyObject *) PyCoro_New(PyFrameObject *,
     PyObject *name, PyObject *qualname);
 
@@ -80,8 +78,6 @@ PyAPI_FUNC(PyObject *) PyAsyncGen_New(PyFrameObject *,
 
 #define PyAsyncGen_CheckExact(op) Py_IS_TYPE(op, &PyAsyncGen_Type)
 
-PyObject *_PyAsyncGenValueWrapperNew(PyObject *);
-
 
 #undef _PyGenObject_HEAD
 
diff --git a/Include/internal/pycore_frame.h b/Include/internal/pycore_frame.h
index 09d41222b61..f8b8e001025 100644
--- a/Include/internal/pycore_frame.h
+++ b/Include/internal/pycore_frame.h
@@ -19,6 +19,8 @@ struct _frame {
     PyObject *_f_frame_data[1];
 };
 
+extern PyFrameObject* _PyFrame_New_NoTrack(PyCodeObject *code);
+
 /* runtime lifecycle */
 
 extern void _PyFrame_Fini(PyInterpreterState *interp);
diff --git a/Include/internal/pycore_function.h b/Include/internal/pycore_function.h
index dc4422df3eb..1c87aa31ddb 100644
--- a/Include/internal/pycore_function.h
+++ b/Include/internal/pycore_function.h
@@ -1,11 +1,18 @@
 #ifndef Py_INTERNAL_FUNCTION_H
 #define Py_INTERNAL_FUNCTION_H
+#ifdef __cplusplus
+extern "C" {
+#endif
 
+#ifndef Py_BUILD_CORE
+#  error "this header requires Py_BUILD_CORE define"
+#endif
 
-#include "Python.h"
-
-PyFunctionObject *
-_PyFunction_FromConstructor(PyFrameConstructor *constr);
+extern PyFunctionObject* _PyFunction_FromConstructor(PyFrameConstructor *constr);
 
+extern uint32_t _PyFunction_GetVersionForCurrentState(PyFunctionObject *func);
 
+#ifdef __cplusplus
+}
+#endif
 #endif /* !Py_INTERNAL_FUNCTION_H */
diff --git a/Include/internal/pycore_genobject.h b/Include/internal/pycore_genobject.h
index 74a676df4ad..42db0d87d1f 100644
--- a/Include/internal/pycore_genobject.h
+++ b/Include/internal/pycore_genobject.h
@@ -8,6 +8,9 @@ extern "C" {
 #  error "this header requires Py_BUILD_CORE define"
 #endif
 
+extern PyObject *_PyGen_yf(PyGenObject *);
+extern PyObject *_PyCoro_GetAwaitableIter(PyObject *o);
+extern PyObject *_PyAsyncGenValueWrapperNew(PyObject *);
 
 /* runtime lifecycle */
 
diff --git a/Python/specialize.c b/Python/specialize.c
index e1db12b853c..1624f1955d4 100644
--- a/Python/specialize.c
+++ b/Python/specialize.c
@@ -1,6 +1,7 @@
 #include "Python.h"
 #include "pycore_code.h"
 #include "pycore_dict.h"
+#include "pycore_function.h"      // _PyFunction_GetVersionForCurrentState()
 #include "pycore_global_strings.h"  // _Py_ID()
 #include "pycore_long.h"
 #include "pycore_moduleobject.h"
@@ -1928,7 +1929,7 @@ void
 _Py_Specialize_BinaryOp(PyObject *lhs, PyObject *rhs, _Py_CODEUNIT *instr,
                         int oparg)
 {
-    assert(_PyOpcode_InlineCacheEntries[BINARY_OP] == 
+    assert(_PyOpcode_InlineCacheEntries[BINARY_OP] ==
            INLINE_CACHE_ENTRIES_BINARY_OP);
     _PyBinaryOpCache *cache = (_PyBinaryOpCache *)(instr + 1);
     switch (oparg) {