From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 26353 invoked by alias); 25 Oct 2004 22:12:48 -0000 Mailing-List: contact gdb-patches-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sources.redhat.com Received: (qmail 26343 invoked from network); 25 Oct 2004 22:12:47 -0000 Received: from unknown (HELO walton.sibelius.xs4all.nl) (82.92.89.47) by sourceware.org with SMTP; 25 Oct 2004 22:12:47 -0000 Received: from elgar.sibelius.xs4all.nl (elgar.sibelius.xs4all.nl [192.168.0.2]) by walton.sibelius.xs4all.nl (8.13.0/8.13.0) with ESMTP id i9PMCRI5004474; Tue, 26 Oct 2004 00:12:27 +0200 (CEST) Received: from elgar.sibelius.xs4all.nl (localhost [127.0.0.1]) by elgar.sibelius.xs4all.nl (8.12.6p3/8.12.6) with ESMTP id i9PMCRAj031729; Tue, 26 Oct 2004 00:12:27 +0200 (CEST) (envelope-from kettenis@elgar.sibelius.xs4all.nl) Received: (from kettenis@localhost) by elgar.sibelius.xs4all.nl (8.12.6p3/8.12.6/Submit) id i9PMCQhJ031724; Tue, 26 Oct 2004 00:12:26 +0200 (CEST) Date: Mon, 25 Oct 2004 22:12:00 -0000 Message-Id: <200410252212.i9PMCQhJ031724@elgar.sibelius.xs4all.nl> From: Mark Kettenis To: drow@false.org CC: gdb-patches@sources.redhat.com, ezannoni@redhat.com, cagney@gnu.org, roland@redhat.com In-reply-to: <20041024231636.GA21927@nevyn.them.org> (message from Daniel Jacobowitz on Sun, 24 Oct 2004 19:16:36 -0400) Subject: Re: [rfa] Attach vsyscall support for GNU/Linux References: <20041024185345.GB22700@nevyn.them.org> <200410242054.i9OKsjnl028328@elgar.sibelius.xs4all.nl> <20041024231636.GA21927@nevyn.them.org> X-SW-Source: 2004-10/txt/msg00418.txt.bz2 Date: Sun, 24 Oct 2004 19:16:36 -0400 From: Daniel Jacobowitz Thanks for the explanation Daniel! Unwinding bugs aside, I think it's valuable for GDB to know that it is at a signal trampoline. I think the custom display in backtrace is valuable. That means we should look for signal handlers before looking for CFI. For NPTL that value judgement would fall the other way - not having to special-case signal handlers is a clear win. Given the fact that it is desirable for GDB to know that it's dealing with a signal handler, I think the correct approach is to extend the DWARF2 unwinder with a method to get the frame type, similar to what we already do for pre-initializing the register state. I'll see if I can come up with a patch for you to test. Cheers, Mark