From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 24343 invoked by alias); 10 Sep 2005 15:29:32 -0000 Mailing-List: contact gdb-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sources.redhat.com Received: (qmail 24281 invoked by uid 22791); 10 Sep 2005 15:29:18 -0000 Received: from nevyn.them.org (HELO nevyn.them.org) (66.93.172.17) by sourceware.org (qpsmtpd/0.30-dev) with ESMTP; Sat, 10 Sep 2005 15:29:18 +0000 Received: from drow by nevyn.them.org with local (Exim 4.52) id 1EE7I3-0000sX-Dh; Sat, 10 Sep 2005 11:29:15 -0400 Date: Sat, 10 Sep 2005 15:29:00 -0000 From: Daniel Jacobowitz To: David Lecomber Cc: gdb Subject: Re: Itanium and GDB on 2.6.x kernels with pthreads Message-ID: <20050910152915.GA2637@nevyn.them.org> Mail-Followup-To: David Lecomber , gdb References: <1126110236.8094.85.camel@delmo.priv.wark.uk.streamline-computing.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1126110236.8094.85.camel@delmo.priv.wark.uk.streamline-computing.com> User-Agent: Mutt/1.5.8i X-SW-Source: 2005-09/txt/msg00063.txt.bz2 On Wed, Sep 07, 2005 at 05:23:56PM +0100, David Lecomber wrote: > Dear all, > > Attached is a simple program, and simple script for GDB (current CVS, > and previous versions) > > gcc -o pf -g pf.c -lm -lpthread > > gdb ./pf < gdb.script > > The script is a break main and then 'next' four times, followed by quit. > > On a 2.4.21 Itanium system, it's quick and quits happily. > > On a 2.6.5 Itanium, it hangs during the later nexts. Does anyone have a > more recent Itanium they could try and see if this is a transient kernel > issue? And on 2.4.27 (-dsa-itanium-smp, on one of Debian's machines, merulo.debian.org) it hangs during the first next. Thread debugging is completely hosed. That's using the installed GDB 6.3. Using a GDB I've built from CVS I get the same result. If I strace gdb, it segfaults at the run command. It's not the same problem you're seeing, because gdb is not consuming CPU. CW: waitpid 17370 received Trace/breakpoint trap (stopped) CW: waitpid 17370 received Trace/breakpoint trap (stopped) CW: waitpid 17370 received Illegal instruction (stopped) [Thread debugging using libthread_db enabled] [New Thread 16384 (LWP 17370)] LLR: PTRACE_SINGLESTEP process 17370, 0 (resume event thread) LLW: waitpid 17370 received Trace/breakpoint trap (stopped) LLW: Candidate event Trace/breakpoint trap (stopped) in LWP 17370. LLTA: PTRACE_PEEKUSER LWP 17370, 0, 0 (OK) SEL: Select single-step LWP 17370 LLW: trap_ptid is process 17370. LLR: PTRACE_CONT process 17370, 0 (resume event thread) LLW: waitpid 17370 received Illegal instruction (stopped) LLW: Candidate event Illegal instruction (stopped) in LWP 17370. LLTA: PTRACE_PEEKUSER LWP 17370, 0, 0 (OK) LLR: PTRACE_SINGLESTEP process 17370, 0 (resume event thread) Those sigill's should not be there, should they? Something is seriously broken in ia64-land... I get them even running single-threaded, but they're ignored because they happen at breakpoints. But I'm not convinced that they don't indicate a real problem somewhere. And single-steps take me nowhere useful, and most local variables can't be displayed. Without knowing something useful about ia64, I don't think I can usefully debug this, and there's no guarantee that it's even the same problem you're seeing. Sorry. -- Daniel Jacobowitz CodeSourcery, LLC