From 4013dbf70a35108b30925d3b04f384ec765ae9b9 Mon Sep 17 00:00:00 2001
From: Vincent Wei <vincent@minigui.org>
Date: Wed, 19 May 2021 08:49:38 +0800
Subject: [PATCH] fix a compilation error

---
 src/include/newgal.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/include/newgal.h b/src/include/newgal.h
index aaa29ba8..8be2c074 100644
--- a/src/include/newgal.h
+++ b/src/include/newgal.h
@@ -438,7 +438,7 @@ void GAL_UpdateRect
                 (GAL_Surface *screen, Sint32 x, Sint32 y, Uint32 w, Uint32 h);
 
 #ifdef _MGUSE_UPDATE_REGION
-BLOCKHEAP __mg_free_update_region_list;
+extern BLOCKHEAP __mg_free_update_region_list;
 #endif
 
 BOOL GAL_SyncUpdate (GAL_Surface *screen);