From 23e3887e05ab650f1dd695767181c76fea2e5b77 Mon Sep 17 00:00:00 2001
From: root <root@ubuntu-14.04-amd64-vbox>
Date: Fri, 10 Jul 2015 18:06:06 +0000
Subject: [PATCH] avoid infinite loop with GCCGO

Signed-off-by: Srini Brahmaroutu <srbrahma@us.ibm.com>
---
 libcontainer/stacktrace/capture.go | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/libcontainer/stacktrace/capture.go b/libcontainer/stacktrace/capture.go
index 15b3482c..5ee6e37a 100644
--- a/libcontainer/stacktrace/capture.go
+++ b/libcontainer/stacktrace/capture.go
@@ -9,13 +9,17 @@ func Capture(userSkip int) Stacktrace {
 	var (
 		skip   = userSkip + 1 // add one for our own function
 		frames []Frame
+		prevPc uintptr = 0
 	)
 	for i := skip; ; i++ {
 		pc, file, line, ok := runtime.Caller(i)
-		if !ok {
+		//detect if caller is repeated to avoid loop, gccgo
+		//currently runs  into a loop without this check
+		if !ok || pc == prevPc {
 			break
 		}
 		frames = append(frames, NewFrame(pc, file, line))
+		prevPc = pc
 	}
 	return Stacktrace{
 		Frames: frames,