diff --git a/Source/CTest/Curl/Testing/curltest.c b/Source/CTest/Curl/Testing/curltest.c
index 0037e11bd..c21774a08 100644
--- a/Source/CTest/Curl/Testing/curltest.c
+++ b/Source/CTest/Curl/Testing/curltest.c
@@ -1,4 +1,4 @@
-// Prevent warnings on Visual Studio
+/* Prevent warnings on Visual Studio */
 struct _RPC_ASYNC_STATE;
 
 #include "curl/curl.h"