From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 91308 invoked by alias); 10 Jul 2019 00:28:14 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Received: (qmail 91298 invoked by uid 89); 10 Jul 2019 00:28:13 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-1.9 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS autolearn=ham version=3.3.1 spammy= X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Wed, 10 Jul 2019 00:28:11 +0000 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 4ED9C308210D; Wed, 10 Jul 2019 00:28:09 +0000 (UTC) Received: from localhost.localdomain (ovpn-112-18.rdu2.redhat.com [10.10.112.18]) by smtp.corp.redhat.com (Postfix) with ESMTP id 605355F9C8; Wed, 10 Jul 2019 00:28:03 +0000 (UTC) Subject: Re: [PATCH,RFC,V3 0/5] Support for CTF in GCC To: Segher Boessenkool , Nix Cc: Richard Biener , Indu Bhagat , Indu Bhagat , GCC Patches References: <1561617445-9328-1-git-send-email-indu.bhagat@oracle.com> <0086f709-b8e5-fc73-1679-4a39e0f4e673@redhat.com> <755cd109-f02b-3ebd-762f-71ae570bf21a@oracle.com> <87k1cwwd37.fsf@esperi.org.uk> <20190709232514.GB14074@gate.crashing.org> From: Jeff Law Openpgp: preference=signencrypt Message-ID: Date: Wed, 10 Jul 2019 00:50:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 MIME-Version: 1.0 In-Reply-To: <20190709232514.GB14074@gate.crashing.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-IsSubscribed: yes X-SW-Source: 2019-07/txt/msg00752.txt.bz2 On 7/9/19 5:25 PM, Segher Boessenkool wrote: > On Fri, Jul 05, 2019 at 07:28:12PM +0100, Nix wrote: >> On 5 Jul 2019, Richard Biener said: >> >>> On Fri, Jul 5, 2019 at 12:21 AM Indu Bhagat wrote: >>>> CTF, at this time, is type information for entities at global or file scope. >>>> This can be used by online debuggers, program tracers (dynamic tracing); More >>>> generally, it provides type introspection for C programs, with an optional >>>> library API to allow them to get at their own types quite more easily than >>>> DWARF. So, the umbrella usecases are - all C programs that want to introspect >>>> their own types quickly; and applications that want to introspect other >>>> programs's types quickly. >>> >>> What makes it superior to DWARF stripped down to the above feature set? >> >> Increased compactness. > > Does CTF support something like -fasynchronous-unwind-tables? You need > that to have any sane debugging on many platforms. Without it, you > even have only partial backtraces, on most architectures/ABIs anyway. I'd be suprised if it did since you need location information. FWIW, low level libraries like glibc depend on this stuff to support cancellation. jeff