diff --git a/dlls/gdi.exe16/gdi.c b/dlls/gdi.exe16/gdi.c
index f0c354bb1c4..006dd839473 100644
--- a/dlls/gdi.exe16/gdi.c
+++ b/dlls/gdi.exe16/gdi.c
@@ -3048,7 +3048,7 @@ BOOL16 WINAPI IsGDIObject16( HGDIOBJ16 handle16 )
 
     UINT type = GetObjectType( HGDIOBJ_32( handle16 ));
 
-    if (type >= sizeof(type_map)/sizeof(type_map[0])) return FALSE;
+    if (type >= ARRAY_SIZE(type_map)) return FALSE;
     return type_map[type];
 }