fix encoding bug in file path handling

Cython/Compiler/Scanning.py

@@ -206,7 +206,7 @@ class FileSourceDescriptor(SourceDescriptor):
 
     def get_error_description(self):
         path = self.filename
-        cwd = os.getcwd() + os.path.sep
+        cwd = Utils.decode_filename(os.getcwd() + os.path.sep)
         if path.startswith(cwd):
             return path[len(cwd):]
         return path