diff --git a/src/video/win32_v.cpp b/src/video/win32_v.cpp
--- a/src/video/win32_v.cpp
+++ b/src/video/win32_v.cpp
@@ -424,7 +424,7 @@ LRESULT CALLBACK WndProcGdi(HWND hwnd, U
 
 		case WM_PALETTECHANGED:
 			if ((HWND)wParam == hwnd) return 0;
-			FALLTHROUGH;
+			[[fallthrough]];
 
 		case WM_QUERYNEWPALETTE:
 			video_driver->PaletteChanged(hwnd);