Index: Python/pythonrun.c
===================================================================
--- Python/pythonrun.c	(révision 81190)
+++ Python/pythonrun.c	(copie de travail)
@@ -712,8 +712,8 @@
     PyErr_Clear();
     fprintf(stderr,
             "Unable to get the locale encoding: "
-            "fallback to utf-8\n");
-    Py_FileSystemDefaultEncoding = "utf-8";
+            "fallback to ascii\n");
+    Py_FileSystemDefaultEncoding = "ascii";
     Py_HasFileSystemDefaultEncoding = 1;
 #endif
 
Index: Python/bltinmodule.c
===================================================================
--- Python/bltinmodule.c	(révision 81190)
+++ Python/bltinmodule.c	(copie de travail)
@@ -29,7 +29,7 @@
 const char *Py_FileSystemDefaultEncoding = NULL; /* set by initfsencoding() */
 int Py_HasFileSystemDefaultEncoding = 0;
 #else
-const char *Py_FileSystemDefaultEncoding = "utf-8";
+const char *Py_FileSystemDefaultEncoding = "ascii";
 int Py_HasFileSystemDefaultEncoding = 1;
 #endif
 
Index: Objects/unicodeobject.c
===================================================================
--- Objects/unicodeobject.c	(révision 81189)
+++ Objects/unicodeobject.c	(copie de travail)
@@ -1612,7 +1612,7 @@
                                 "surrogateescape");
     }
     else {
-        return PyUnicode_DecodeUTF8(s, size, "surrogateescape");
+        return PyUnicode_DecodeASCII(s, size, "surrogateescape");
     }
 }