From 81d404979780386ecd1756a41dfc09497e194f26 Mon Sep 17 00:00:00 2001
From: Araq <rumpf_a@web.de>
Date: Wed, 30 Apr 2014 01:05:52 +0200
Subject: [PATCH] bugfix: MS-GC GC_unref

---
 lib/system/gc_ms.nim | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/system/gc_ms.nim b/lib/system/gc_ms.nim
index db437b8d0f..410243528e 100644
--- a/lib/system/gc_ms.nim
+++ b/lib/system/gc_ms.nim
@@ -143,7 +143,7 @@ proc nimGCref(p: pointer) {.compilerProc.} =
 
 proc nimGCunref(p: pointer) {.compilerProc.} =
   let cell = usrToCell(p)
-  var L = gch.additionalRoots.len
+  var L = gch.additionalRoots.len-1
   var i = L
   let d = gch.additionalRoots.d
   while i >= 0:
@@ -151,6 +151,7 @@ proc nimGCunref(p: pointer) {.compilerProc.} =
       d[i] = d[L]
       dec gch.additionalRoots.len
       break
+    dec(i)
   when false:
     when withBitvectors: incl(gch.allocated, usrToCell(p))
     else: usrToCell(p).refcount = rcWhite