diff --git a/cpp_17.gypi b/cpp_17.gypi
index 0d62eb218..cec950e37 100644
--- a/cpp_17.gypi
+++ b/cpp_17.gypi
@@ -15,7 +15,7 @@
         '/std:c++17'
       ],
       'AdditionalOptions/': [
-        ['exclude', '^[/-]std:(?!c\+\+17)']
+        ['exclude', '^[/\-]std:(?!c\+\+17)']
       ]
 		}
 	}