From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 5500 invoked by alias); 30 Apr 2007 13:53:12 -0000 Received: (qmail 5488 invoked by uid 22791); 30 Apr 2007 13:53:10 -0000 X-Spam-Check-By: sourceware.org Received: from return.false.org (HELO return.false.org) (66.207.162.98) by sourceware.org (qpsmtpd/0.31) with ESMTP; Mon, 30 Apr 2007 14:53:07 +0100 Received: from return.false.org (localhost [127.0.0.1]) by return.false.org (Postfix) with ESMTP id BAEB84B26F; Mon, 30 Apr 2007 08:53:05 -0500 (CDT) Received: from caradoc.them.org (dsl093-172-095.pit1.dsl.speakeasy.net [66.93.172.95]) by return.false.org (Postfix) with ESMTP id 8F3164B26D; Mon, 30 Apr 2007 08:53:05 -0500 (CDT) Received: from drow by caradoc.them.org with local (Exim 4.67) (envelope-from ) id 1HiWJH-00020S-Li; Mon, 30 Apr 2007 09:52:59 -0400 Date: Mon, 30 Apr 2007 14:12:00 -0000 From: Daniel Jacobowitz To: Luis Machado Cc: Ulrich Weigand , gdb-patches ml Subject: Re: [RFC] Detecting and printing 128-bit long double values for PPC Message-ID: <20070430135259.GA7430@caradoc.them.org> Mail-Followup-To: Luis Machado , Ulrich Weigand , gdb-patches ml References: <1177803916.6280.64.camel@localhost> <200704301227.l3UCRhMP024148@d12av02.megacenter.de.ibm.com> <20070430123432.GA30827@caradoc.them.org> <1177938530.15264.9.camel@localhost> <20070430131616.GB25539@caradoc.them.org> <1177940660.15264.23.camel@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1177940660.15264.23.camel@localhost> User-Agent: Mutt/1.5.15 (2007-04-09) X-IsSubscribed: yes 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: 2007-04/txt/msg00419.txt.bz2 On Mon, Apr 30, 2007 at 10:44:20AM -0300, Luis Machado wrote: > > This is "the ABI-defined long double type", which GDB distinguishes > > from "the debug info describing long double". I suppose you could > > come up with a way to distinguish binaries based on what their debug > > info has to say about it, if it mentions long double anywhere. > > The idea could be that in case a different type is defined in the debug > info than it's in the DWARF info, GDB would stick with what the debug > info says instead. > > But then we would rely on debugging info for performing type > identification. What about debugging running processes that do not have > explicit debug info? That's exactly the problem. For the future, I'll try to solve this using binary tagging. But for now, I think a user-settable option may be the best we can do. Does anyone see a better way? It may be OK to default to 128-bit long double, since 64-bit long double "more or less" works anyway. BTW, the easiest way to see that GDB sometimes uses its builtin types is to start GDB without any executable, and: (gdb) p sizeof(1.) $1 = 8 (gdb) p sizeof(1.f) $2 = 4 (gdb) p sizeof(1.L) $3 = 12 -- Daniel Jacobowitz CodeSourcery