From b8d40172ce2a724ecb125746f37aee989ced5ac9 Mon Sep 17 00:00:00 2001
From: Dmitriy Vyukov <dvyukov@google.com>
Date: Fri, 14 Mar 2014 21:11:04 +0400
Subject: [PATCH] runtime: do not shrink stacks GOCOPYSTACK=0

LGTM=rsc
R=golang-codereviews
CC=golang-codereviews, khr, rsc
https://golang.org/cl/76070043
---
 src/pkg/runtime/stack.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/pkg/runtime/stack.c b/src/pkg/runtime/stack.c
index d580665e2bd..81005de5d7b 100644
--- a/src/pkg/runtime/stack.c
+++ b/src/pkg/runtime/stack.c
@@ -776,6 +776,8 @@ runtime·shrinkstack(G *gp)
 	uintptr used, oldsize, newsize;
 	MSpan *span;
 
+	if(!runtime·copystack)
+		return;
 	oldstk = (byte*)gp->stackguard - StackGuard;
 	oldbase = (byte*)gp->stackbase + sizeof(Stktop);
 	oldsize = oldbase - oldstk;