3 files changed, 12 insertions, 5 deletions
diff --git a/Include/internal/pycore_coreconfig.h b/Include/internal/pycore_coreconfig.h
index 8af310d2b0..d48904e482 100644
--- a/Include/internal/pycore_coreconfig.h
+++ b/Include/internal/pycore_coreconfig.h
@@ -106,12 +106,9 @@ PyAPI_FUNC(_PyInitError) _PyCoreConfig_Copy(
     _PyCoreConfig *config,
     const _PyCoreConfig *config2);
 PyAPI_FUNC(_PyInitError) _PyCoreConfig_SetString(
-    char **config_str,
-    const char *str);
-PyAPI_FUNC(_PyInitError) _PyCoreConfig_SetWideString(
     wchar_t **config_str,
     const wchar_t *str);
-PyAPI_FUNC(_PyInitError) _PyCoreConfig_SetWideStringFromString(
+PyAPI_FUNC(_PyInitError) _PyCoreConfig_DecodeLocale(
     wchar_t **config_str,
     const char *str);
 PyAPI_FUNC(_PyInitError) _PyCoreConfig_InitPathConfig(_PyCoreConfig *config);
diff --git a/Include/internal/pycore_pylifecycle.h b/Include/internal/pycore_pylifecycle.h
index a2383d476e..321cc5d278 100644
--- a/Include/internal/pycore_pylifecycle.h
+++ b/Include/internal/pycore_pylifecycle.h
@@ -21,6 +21,9 @@ extern int _Py_SetFileSystemEncoding(
     const char *errors);
 extern void _Py_ClearFileSystemEncoding(void);
 extern _PyInitError _PyUnicode_InitEncodings(PyInterpreterState *interp);
+#ifdef MS_WINDOWS
+extern int _PyUnicode_EnableLegacyWindowsFSEncoding(void);
+#endif
 
 PyAPI_FUNC(void) _Py_ClearStandardStreamEncoding(void);
 
diff --git a/Include/internal/pycore_pystate.h b/Include/internal/pycore_pystate.h
index 2c24f679dc..67bcd147e2 100644
--- a/Include/internal/pycore_pystate.h
+++ b/Include/internal/pycore_pystate.h
@@ -56,7 +56,14 @@ struct _is {
     PyObject *codec_search_cache;
     PyObject *codec_error_registry;
     int codecs_initialized;
-    int fscodec_initialized;
+
+    /* fs_codec.encoding is initialized to NULL.
+       Later, it is set to a non-NULL string by _PyUnicode_InitEncodings(). */
+    struct {
+        char *encoding;   /* Filesystem encoding (encoded to UTF-8) */
+        char *errors;     /* Filesystem errors (encoded to UTF-8) */
+        _Py_error_handler error_handler;
+    } fs_codec;
 
     _PyCoreConfig core_config;
 #ifdef HAVE_DLOPEN