diff --git a/vyper/ast/validation.py b/vyper/ast/validation.py
index 7742d60c01..36a6a0484c 100644
--- a/vyper/ast/validation.py
+++ b/vyper/ast/validation.py
@@ -48,7 +48,7 @@ def validate_call_args(
             arg_count = (arg_count[0], 2**64)
 
         if arg_count[0] == arg_count[1]:
-            arg_count == arg_count[0]
+            arg_count = arg_count[0]
 
     if isinstance(node.func, vy_ast.Attribute):
         msg = f" for call to '{node.func.attr}'"