From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugs-return-487798-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org>
Received: (qmail 31010 invoked by alias); 2 Jun 2015 09:00:26 -0000
Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm
Precedence: bulk
List-Id: <gcc-bugs.gcc.gnu.org>
List-Archive: <http://gcc.gnu.org/ml/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-help@gcc.gnu.org>
Sender: gcc-bugs-owner@gcc.gnu.org
Received: (qmail 30924 invoked by uid 48); 2 Jun 2015 09:00:22 -0000
From: "vogt at linux dot vnet.ibm.com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug go/66303] runtime.Caller() returns infinitely deep stack frames on s390x
Date: Tue, 02 Jun 2015 09:00:00 -0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: go
X-Bugzilla-Version: 5.1.1
X-Bugzilla-Keywords:
X-Bugzilla-Severity: normal
X-Bugzilla-Who: vogt at linux dot vnet.ibm.com
X-Bugzilla-Status: UNCONFIRMED
X-Bugzilla-Resolution:
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: ian at airs dot com
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags:
X-Bugzilla-Changed-Fields: cc
Message-ID: <bug-66303-4-6VwqTprlYD@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-66303-4@http.gcc.gnu.org/bugzilla/>
References: <bug-66303-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-SW-Source: 2015-06/txt/msg00130.txt.bz2

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66303

Dominik Vogt <vogt at linux dot vnet.ibm.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |vogt at linux dot vnet.ibm.com

--- Comment #4 from Dominik Vogt <vogt at linux dot vnet.ibm.com> ---
I think the problem is that in the backtrace below
_Unwind_Find_registered_FDE() is called with a pc that points one byte before
the start of main.main (0x80001de8).  That is cause by this line from
uw_frame_state_for():

  fde = _Unwind_Find_FDE (context->ra + _Unwind_IsSignalFrame (context) - 1,
                          &context->bases);

-- snip --
#0  _Unwind_Find_registered_FDE (bases=0xc2084176e0, 
    pc=0x80001de7 <main.main+23>) at ../../../libgcc/unwind-dw2-fde.c:1010
#1  _Unwind_Find_FDE (pc=0x80001de7 <main.main+23>, bases=0xc2084176e0)
    at ../../../libgcc/unwind-dw2-fde-dip.c:454
#2  0x000003fff6ee665c in uw_frame_state_for (
    context=context@entry=0xc2084175b0, fs=fs@entry=0xc208417738)
    at ../../../libgcc/unwind-dw2.c:1241
#3  0x000003fff6ee8442 in _Unwind_Backtrace (trace=0x3fff7aca438 <unwind>, 
    trace_argument=0xc208417aa8) at ../../../libgcc/unwind.inc:290
#4  0x000003fff7aca51a in backtrace_full (state=<optimized out>, 
    skip=<optimized out>, callback=<optimized out>, 
    error_callback=<optimized out>, data=0xc208417b78)
    at ../../../libbacktrace/backtrace.c:106
#5  0x000003fff7773a16 in runtime_callers (skip=<optimized out>, 
    locbuf=<optimized out>, m=<optimized out>, keep_thunks=<optimized out>)
    at ../../../libgo/runtime/go-callers.c:168
#6  0x000003fff777356c in runtime.Caller (skip=skip@entry=20)
    at ../../../libgo/runtime/go-caller.c:168
#7  0x0000000080001de8 in main.main () at pr66303.go:9
-- snip --