From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 4791 invoked by alias); 15 Feb 2010 18:40:59 -0000 Received: (qmail 4779 invoked by uid 22791); 15 Feb 2010 18:40:58 -0000 X-SWARE-Spam-Status: No, hits=-2.5 required=5.0 tests=AWL,BAYES_00,SPF_PASS X-Spam-Check-By: sourceware.org Received: from mail.codesourcery.com (HELO mail.codesourcery.com) (38.113.113.100) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Mon, 15 Feb 2010 18:40:54 +0000 Received: (qmail 30010 invoked from network); 15 Feb 2010 18:40:53 -0000 Received: from unknown (HELO caradoc.them.org) (dan@127.0.0.2) by mail.codesourcery.com with ESMTPA; 15 Feb 2010 18:40:53 -0000 Date: Mon, 15 Feb 2010 18:40:00 -0000 From: Daniel Jacobowitz To: Jan Kratochvil Cc: gdb-patches@sourceware.org Subject: Re: [patch] STT_GNU_IFUNC support Message-ID: <20100215184048.GA16276@caradoc.them.org> Mail-Followup-To: Jan Kratochvil , gdb-patches@sourceware.org References: <20100214203512.GA838@host0.dyn.jankratochvil.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100214203512.GA838@host0.dyn.jankratochvil.net> User-Agent: Mutt/1.5.20 (2009-06-14) Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2010-02/txt/msg00371.txt.bz2 On Sun, Feb 14, 2010 at 09:35:12PM +0100, Jan Kratochvil wrote: > This implementation resolves ifunc in an uncached way by an inferior call any > time the symbol resolution is needed. It does not try to pick out the jump > address value from ".got.plt" as filled there by ld.so. (GDB stepping into > library functions also does not try to do so.) Do you mean that "print strcmp" or "break strcmp" is now going to do an inferior call? That doesn't seem like a good idea to me. I would like for some other maintainers to comment though. Inferior calls are very slow, and they can go wrong (pending signals, misbehaving programs, etc). I believe we should make an effort to minimize them. For user messages, maybe we should call these "indirect functions"; that's what ifunc is short for. -- Daniel Jacobowitz CodeSourcery