add safety fix for Python globals in debug writer

diff --git a/Cython/Compiler/ParseTreeTransforms.py b/Cython/Compiler/ParseTreeTransforms.py
index 99eb5fd..aac413e 100644 (file)
--- a/Cython/Compiler/ParseTreeTransforms.py
+++ b/Cython/Compiler/ParseTreeTransforms.py
@@ -2891,6 +2891,9 @@ class DebugTransform(CythonTransform):
 
     def serialize_local_variables(self, entries):
         for entry in entries.values():
+            if not entry.cname:
+                # not a local variable
+                continue
             if entry.type.is_pyobject:
                 vartype = 'PythonObject'
             else: