Patch #1272, by Christian Heimes and Alexandre Vassalotti.
Changes to make __file__ a proper Unicode object, using the default
filesystem encoding.
This is a bit tricky because the default filesystem encoding isn't
set by the time we import the first modules; at that point we fudge
things a bit.  This is okay since __file__ isn't really used much
except for error reporting.
Tested on OSX and Linux only so far.
diff --git a/Python/pythonrun.c b/Python/pythonrun.c
index a37a3e4..4e239c9 100644
--- a/Python/pythonrun.c
+++ b/Python/pythonrun.c
@@ -867,7 +867,8 @@
 		return -1;
 	d = PyModule_GetDict(m);
 	if (PyDict_GetItemString(d, "__file__") == NULL) {
-		PyObject *f = PyString_FromString(filename);
+		PyObject *f;
+		f = PyUnicode_DecodeFSDefault(filename);
 		if (f == NULL)
 			return -1;
 		if (PyDict_SetItemString(d, "__file__", f) < 0) {