diff --git a/src/vim.h b/src/vim.h
index 898ebb6..8d49dcd 100644
--- a/src/vim.h
+++ b/src/vim.h
@@ -1632,14 +1632,14 @@
 #  define GUI_FUNCTION2(f, pixel)   (gui.in_use \
 				    ?  ((pixel) != INVALCOLOR \
 					? gui_##f((pixel)) \
-					: (long_u)INVALCOLOR) \
+					: INVALCOLOR) \
 				    : termgui_##f((pixel)))
 #  define USE_24BIT		    (gui.in_use || p_tgc)
 # else
 #  define GUI_FUNCTION(f)	    gui_##f
 #  define GUI_FUNCTION2(f,pixel)    ((pixel) != INVALCOLOR \
 				     ? gui_##f((pixel)) \
-				     : (long_u)INVALCOLOR)
+				     : INVALCOLOR)
 #  define USE_24BIT		    gui.in_use
 # endif
 #else