@@ -183,6 +183,10 @@ PyAPI_FUNC(int) _Py_GetLocaleconvNumeric(
 
 #endif   /* Py_LIMITED_API */
 
+#ifdef Py_BUILD_CORE
+PyAPI_FUNC(int) _Py_GetForceASCII(void);
+#endif
+
 #ifdef __cplusplus
 }
 #endif
 
@@ -180,6 +180,18 @@ check_force_ascii(void)
     return 1;
 }
 
+
+int
+_Py_GetForceASCII(void)
+{
+    if (force_ascii == -1) {
+        force_ascii = check_force_ascii();
+    }
+    return force_ascii;
+}
+
+
+
 static int
 encode_ascii(const wchar_t *text, char **str,
              size_t *error_pos, const char **reason,
 
@@ -1615,6 +1615,10 @@ initfsencoding(PyInterpreterState *interp)
         Py_FileSystemDefaultEncoding = "utf-8";
         Py_HasFileSystemDefaultEncoding = 1;
     }
+    else if (_Py_GetForceASCII()) {
+        Py_FileSystemDefaultEncoding = "ascii";
+        Py_HasFileSystemDefaultEncoding = 1;
+    }
     else if (Py_FileSystemDefaultEncoding == NULL) {
         Py_FileSystemDefaultEncoding = get_locale_encoding();
         if (Py_FileSystemDefaultEncoding == NULL) {
Original file line number	Diff line number	Diff line change
`@@ -183,6 +183,10 @@ PyAPI_FUNC(int) _Py_GetLocaleconvNumeric(`
`183`	`183`
`184`	`184`	`#endif /* Py_LIMITED_API */`
`185`	`185`
	`186`	`+#ifdef Py_BUILD_CORE`
	`187`	`+PyAPI_FUNC(int) _Py_GetForceASCII(void);`
	`188`	`+#endif`
	`189`	`+`
`186`	`190`	`#ifdef __cplusplus`
`187`	`191`	`}`
`188`	`192`	`#endif`