diff --git a/simpledisplay.d b/simpledisplay.d
index b445b29..d7249cf 100644
--- a/simpledisplay.d
+++ b/simpledisplay.d
@@ -7504,7 +7504,7 @@ version(Windows) {
 	// Mix this into the SimpleWindow class
 	mixin template NativeSimpleWindowImplementation() {
 		int curHidden = 0; // counter
-		static bool[string] knownWinClasses;
+		__gshared static bool[string] knownWinClasses;
 		static bool altPressed = false;
 
 		HANDLE oldCursor;