Adding support for offsetof()
diff --git a/tests/test_c_lexer.py b/tests/test_c_lexer.py
index 6d0b52d..033963e 100644
--- a/tests/test_c_lexer.py
+++ b/tests/test_c_lexer.py
@@ -84,6 +84,9 @@
         # - is MINUS, the rest a constnant
         self.assertTokensTypes('-1', ['MINUS', 'INT_CONST_DEC'])
 
+    def test_special_names(self):
+        self.assertTokensTypes('sizeof offsetof', ['SIZEOF', 'OFFSETOF'])
+
     def test_floating_constants(self):
         self.assertTokensTypes('1.5f', ['FLOAT_CONST'])
         self.assertTokensTypes('01.5', ['FLOAT_CONST'])