Try to get hg to treat importlib.h as binary.
diff --git a/Python/freeze_importlib.py b/Python/freeze_importlib.py
index a069a0b..9cce0b1 100644
--- a/Python/freeze_importlib.py
+++ b/Python/freeze_importlib.py
@@ -24,6 +24,7 @@
     lines.append('};\n')
     with open(output_path, 'w') as output_file:
         output_file.write('\n'.join(lines))
+        output_file.write('\u0000')
 
 
 if __name__ == '__main__':
diff --git a/Python/importlib.h b/Python/importlib.h
index 6980231..f11dcbb 100644
--- a/Python/importlib.h
+++ b/Python/importlib.h
Binary files differ