safety fix for analysis in assigned builtin methods optimisation

--HG--
extra : rebase_source : 8a7842eea9d10b4e8054ed3782e0efdc2b2ce02c

Cython/Compiler/Visitor.py

@@ -551,7 +551,7 @@ class MethodDispatcherTransform(EnvTransform):
             if not value.entry or len(value.entry.cf_assignments) > 1:
                 # the variable might have been reassigned => play safe
                 return node
-        elif value.is_attribute:
+        elif value.is_attribute and value.obj.is_name:
             if not value.obj.entry or len(value.obj.entry.cf_assignments) > 1:
                 # the underlying variable might have been reassigned => play safe
                 return node