diff --git a/CMakeLists.txt b/CMakeLists.txt
index da7f72d3d..d481d0523 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -293,8 +293,10 @@ if(WIN32)
   set(REGEX_MALLOC 1)
   set(USE_GENERIC_MS_NINT 1)
   set(HAVE_STRING_H 0)
-  # Suppress warnings for regex.c
-  set_source_files_properties(${REGEX_SOURCES} PROPERTIES COMPILE_FLAGS /w)
+  if(MSVC)
+    # Suppress warnings for regex.c
+    set_source_files_properties(${REGEX_SOURCES} PROPERTIES COMPILE_FLAGS /w)
+  endif(MSVC)
 else(WIN32)
   set(REGEX_SOURCES "")
 endif(WIN32)