From 61b4b4adf96496dd00c1191a455524bef682db4b Mon Sep 17 00:00:00 2001
From: Vincent Wei <vincent@minigui.org>
Date: Mon, 3 Feb 2020 17:57:29 +0800
Subject: [PATCH] check shared_header

---
 src/gui/window.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/gui/window.c b/src/gui/window.c
index e2b5b8ea..453b7420 100644
--- a/src/gui/window.c
+++ b/src/gui/window.c
@@ -3828,8 +3828,10 @@ HWND GUIAPI CreateMainWindowEx2 (PMAINWINCREATE pCreateInfo,
 
 #ifdef _MGSCHEMA_COMPOSITING
     // Close file descriptor to free kernel memory?
-    close (pWin->surf->shared_header->fd);
-    pWin->surf->shared_header->fd = -1;
+    if (pWin->surf->shared_header) {
+        close (pWin->surf->shared_header->fd);
+        pWin->surf->shared_header->fd = -1;
+    }
 #endif
 
     return (HWND)pWin;