From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 6359 invoked by alias); 16 Feb 2006 15:28:51 -0000 Received: (qmail 6338 invoked by uid 22791); 16 Feb 2006 15:28:50 -0000 X-Spam-Check-By: sourceware.org Received: from potter.codesourcery.com (HELO mail.codesourcery.com) (65.74.133.4) by sourceware.org (qpsmtpd/0.31) with ESMTP; Thu, 16 Feb 2006 15:28:50 +0000 Received: (qmail 1569 invoked from network); 16 Feb 2006 15:28:48 -0000 Received: from unknown (HELO 81-178-226-166.dsl.pipex.com) (paul@127.0.0.2) by mail.codesourcery.com with ESMTPA; 16 Feb 2006 15:28:48 -0000 From: Paul Brook To: Richard Guenther Subject: Re: gfortran and -mlong-double-128 Date: Thu, 16 Feb 2006 15:28:00 -0000 User-Agent: KMail/1.9.1 Cc: gcc@gcc.gnu.org, =?iso-8859-1?q?Fran=E7ois-Xavier_Coudert?= , gfortran References: <19c433eb0602160309y754cf258kd00227b6d80bff2b@mail.gmail.com> <200602161503.54114.paul@codesourcery.com> <84fc9c000602160718y4f4cd8c0v574924cc9ff2ea45@mail.gmail.com> In-Reply-To: <84fc9c000602160718y4f4cd8c0v574924cc9ff2ea45@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Message-Id: <200602161528.47322.paul@codesourcery.com> Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org X-SW-Source: 2006-02/txt/msg00308.txt.bz2 On Thursday 16 February 2006 15:18, Richard Guenther wrote: > On 2/16/06, Paul Brook wrote: > > On Thursday 16 February 2006 11:09, Fran=E7ois-Xavier Coudert wrote: > > > Hi all, > > > > > > I'm sending this mail because I'm a bit confused about the > > > -mlong-double-128 option on (for example) ppc64-linux, and its impact > > > on gfortran/libgfortran. > > > > Having gfortran magically know about certain ABI breaking options, and > > doing funny things on certain targets seems a very bad precedent to me. > > The point is that from a gfortran perspective -mlong-double-128 doesn't > change the ABI, it merely adds to it (which is sort of a change, but less > invasive than changing long double from 8bytes to 16bytes). So we can > easily cope with the user request for -mlong-double-128 by always providi= ng > the kind=3D16 intrinsics. Except it [potentially] also changes the ABI that libgfortran uses to talk = to=20 glibc. ie. a -mlong-double-128 libgfortran probably won't work with a=20 -mlong-double-64 glibc. Paul