From e53943f8fd43d8a234bd4e9db0c6493f7df79ab5 Mon Sep 17 00:00:00 2001
From: Richard Kistruck <rhsk@ravenbrook.com>
Date: Tue, 29 Apr 2008 15:09:12 +0100
Subject: [PATCH] Mps br auto_header: cannot segfree nailed seg if it has a
 buffer

Copied from Perforce
 Change: 164851
 ServerID: perforce.ravenbrook.com
---
 mps/code/poolamc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mps/code/poolamc.c b/mps/code/poolamc.c
index 5a4d847aa29..39a89c8977f 100644
--- a/mps/code/poolamc.c
+++ b/mps/code/poolamc.c
@@ -1962,10 +1962,10 @@ static void amcReclaimNailed(Pool pool, Trace trace, Seg seg)
     if(amcSegHasNailboard(seg)) {
       amcSegDestroyNailboard(seg, pool);
     }
-    if(emptySeg) {
+    if(emptySeg && (SegBuffer(seg) == NULL)) {
       /* fix .nailboard.limitations.middle */
       amcGen gen = amcSegGen(seg);
-      
+
       --gen->segs;
       gen->pgen.totalSize -= SegSize(seg);