diff --git a/include/sysemu/os-win32.h b/include/sysemu/os-win32.h
index ff18b23db1..d8978e28c0 100644
--- a/include/sysemu/os-win32.h
+++ b/include/sysemu/os-win32.h
@@ -67,8 +67,6 @@ int getpagesize(void);
 # define EPROTONOSUPPORT EINVAL
 #endif
 
-int setenv(const char *name, const char *value, int overwrite);
-
 typedef struct {
     long tv_sec;
     long tv_usec;
diff --git a/os-win32.c b/os-win32.c
index 1336cd34f0..6b86e022f0 100644
--- a/os-win32.c
+++ b/os-win32.c
@@ -30,28 +30,6 @@
 #include "qemu-options.h"
 #include "sysemu/runstate.h"
 
-/***********************************************************/
-/* Functions missing in mingw */
-
-int setenv(const char *name, const char *value, int overwrite)
-{
-    int result = 0;
-    if (overwrite || !getenv(name)) {
-        size_t length = strlen(name) + strlen(value) + 2;
-        char *string = g_malloc(length);
-        snprintf(string, length, "%s=%s", name, value);
-        result = putenv(string);
-
-        /* Windows takes a copy and does not continue to use our string.
-         * Therefore it can be safely freed on this platform.  POSIX code
-         * typically has to leak the string because according to the spec it
-         * becomes part of the environment.
-         */
-        g_free(string);
-    }
-    return result;
-}
-
 static BOOL WINAPI qemu_ctrl_handler(DWORD type)
 {
     qemu_system_shutdown_request(SHUTDOWN_CAUSE_HOST_SIGNAL);
diff --git a/tests/libqtest.c b/tests/libqtest.c
index 91e9cb220c..f36e30a4de 100644
--- a/tests/libqtest.c
+++ b/tests/libqtest.c
@@ -254,7 +254,7 @@ QTestState *qtest_init_without_qmp_handshake(const char *extra_args)
     s->expected_status = 0;
     s->qemu_pid = fork();
     if (s->qemu_pid == 0) {
-        setenv("QEMU_AUDIO_DRV", "none", true);
+        g_setenv("QEMU_AUDIO_DRV", "none", true);
         execlp("/bin/sh", "sh", "-c", command, NULL);
         exit(1);
     }
diff --git a/tests/test-crypto-tlscredsx509.c b/tests/test-crypto-tlscredsx509.c
index a27efb7540..f487349c32 100644
--- a/tests/test-crypto-tlscredsx509.c
+++ b/tests/test-crypto-tlscredsx509.c
@@ -141,7 +141,7 @@ int main(int argc, char **argv)
 
     module_call_init(MODULE_INIT_QOM);
     g_test_init(&argc, &argv, NULL);
-    setenv("GNUTLS_FORCE_FIPS_MODE", "2", 1);
+    g_setenv("GNUTLS_FORCE_FIPS_MODE", "2", 1);
 
     mkdir(WORKDIR, 0700);
 
diff --git a/tests/test-crypto-tlssession.c b/tests/test-crypto-tlssession.c
index 6560d7134f..8b2453fa79 100644
--- a/tests/test-crypto-tlssession.c
+++ b/tests/test-crypto-tlssession.c
@@ -398,7 +398,7 @@ int main(int argc, char **argv)
 
     module_call_init(MODULE_INIT_QOM);
     g_test_init(&argc, &argv, NULL);
-    setenv("GNUTLS_FORCE_FIPS_MODE", "2", 1);
+    g_setenv("GNUTLS_FORCE_FIPS_MODE", "2", 1);
 
     mkdir(WORKDIR, 0700);
 
diff --git a/tests/test-io-channel-tls.c b/tests/test-io-channel-tls.c
index 3c9ef6f941..ad7554c534 100644
--- a/tests/test-io-channel-tls.c
+++ b/tests/test-io-channel-tls.c
@@ -273,7 +273,7 @@ int main(int argc, char **argv)
 
     module_call_init(MODULE_INIT_QOM);
     g_test_init(&argc, &argv, NULL);
-    setenv("GNUTLS_FORCE_FIPS_MODE", "2", 1);
+    g_setenv("GNUTLS_FORCE_FIPS_MODE", "2", 1);
 
     mkdir(WORKDIR, 0700);
 
diff --git a/tests/test-vmstate.c b/tests/test-vmstate.c
index 1e5be1d4ff..8f184f3556 100644
--- a/tests/test-vmstate.c
+++ b/tests/test-vmstate.c
@@ -1325,7 +1325,7 @@ int main(int argc, char **argv)
 
     module_call_init(MODULE_INIT_QOM);
 
-    setenv("QTEST_SILENT_ERRORS", "1", 1);
+    g_setenv("QTEST_SILENT_ERRORS", "1", 1);
 
     g_test_init(&argc, &argv, NULL);
     g_test_add_func("/vmstate/simple/primitive", test_simple_primitive);
diff --git a/ui/sdl2.c b/ui/sdl2.c
index bd4e73661d..9030f1c42e 100644
--- a/ui/sdl2.c
+++ b/ui/sdl2.c
@@ -772,7 +772,7 @@ static void sdl2_display_init(DisplayState *ds, DisplayOptions *o)
      * This is a bit hackish but saves us from bigger problem.
      * Maybe it's a good idea to fix this in SDL instead.
      */
-    setenv("SDL_VIDEODRIVER", "x11", 0);
+    g_setenv("SDL_VIDEODRIVER", "x11", 0);
 #endif
 
     if (SDL_Init(SDL_INIT_VIDEO)) {