diff --git a/clang-tools-extra/test/clang-tidy/modernize-redundant-void-arg.cpp b/clang-tools-extra/test/clang-tidy/modernize-redundant-void-arg.cpp
index 6f23fe682dae..dd758bc10a2d 100644
--- a/clang-tools-extra/test/clang-tidy/modernize-redundant-void-arg.cpp
+++ b/clang-tools-extra/test/clang-tidy/modernize-redundant-void-arg.cpp
@@ -1,6 +1,6 @@
 // RUN: %check_clang_tidy %s modernize-redundant-void-arg %t
 
-#include <iostream>
+#define NULL 0
 
 int foo();