From de6a66851e94180f863aee3f4f4fbd5bb47a2a3e Mon Sep 17 00:00:00 2001
From: "alexey.lysiuk" <alexey.lysiuk@gmail.com>
Date: Thu, 12 Jan 2017 16:24:55 +0200
Subject: [PATCH] Fixed issue with extraction of built GL nodes

See https://mantis.zdoom.org/view.php?id=39
---
 src/nodebuild_extract.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/nodebuild_extract.cpp b/src/nodebuild_extract.cpp
index 11332f049..bdb343449 100644
--- a/src/nodebuild_extract.cpp
+++ b/src/nodebuild_extract.cpp
@@ -123,7 +123,8 @@ void FNodeBuilder::Extract (node_t *&outNodes, int &nodeCount,
 
 			if (segs[i].Partner != DWORD_MAX)
 			{
-				outSegs[i].PartnerSeg = &outSegs[Segs[segs[i].Partner].storedseg];
+				const DWORD storedseg = Segs[segs[i].Partner].storedseg;
+				outSegs[i].PartnerSeg = DWORD_MAX == storedseg ? nullptr : &outSegs[storedseg];
 			}
 			else
 			{