I have been spoiled by chained comparisons in python
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index 53833ad..918ffb6 100644
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -4952,7 +4952,7 @@
             Py_INCREF(Py_NotImplemented); \
             return Py_NotImplemented; \
         } \
-        assert(left->size == right->size == res->size); \
+        assert(left->size == right->size && right->size == res->size); \
         op(res->size, res->set, left->set, right->set); \
         return (PyObject *)res; \
     } \