From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 31158 invoked by alias); 6 May 2018 01:31:23 -0000 Mailing-List: contact libffi-discuss-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libffi-discuss-owner@sourceware.org Received: (qmail 31122 invoked by uid 89); 6 May 2018 01:31:22 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.3 required=5.0 tests=AWL,BAYES_00,HTML_MESSAGE,KAM_SHORT,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.2 spammy=visual, filed, H*c:alternative, c X-HELO: mail-lf0-f67.google.com Received: from mail-lf0-f67.google.com (HELO mail-lf0-f67.google.com) (209.85.215.67) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Sun, 06 May 2018 01:31:19 +0000 Received: by mail-lf0-f67.google.com with SMTP id x7-v6so848744lff.13 for ; Sat, 05 May 2018 18:31:19 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=bES0sgm76DMSCjQSofi2hywwVMTxI823YUIf4/dlFvs=; b=RpB/4BTvcWztKbT2AjrrVf45h1alJ5rTr0hPXtq+RoIH+cI9Hsci1k6cs7yZvIbClG UcajyurBLAPvESfsZ+iTVIa+CNaH+AMrybz5oHXmSolc7Zani8cLheSXKOxBk6JnL1K7 tsVVU/Bri55MtUZhsqXwFt23nWCa1H1w34z/7KlMmJZsc2D2dgo1njVtXcmraqIwcm3+ vzQ4vXnlzmkChPsabWvC5/piID7sT+3848qfRvl2AZjeEZDI3qokE5pB3ljhYU2O1VvH z5ScWFY7xK0/4LvzQRuKrCWMMWcUxWFrlAkz6jy+zDo9s7P+jh+D40d2jbSs1mOjd7k9 FJhw== X-Gm-Message-State: ALQs6tCOwhItLufS1DxZWN3ripw7EGan+ZKRkI0Pb2nB86+TI3eBKg4g aT6Q9wMAB/11B9hqsyze1IxBJ6NgUBhv/K1lOiBVCA== X-Google-Smtp-Source: AB8JxZpDMfqnt6IA9aJbyrRl1Wj2p1gYlnwvf8kshNSMcjHVIePSIY9Z2rT5Z5J5mZJCQlRIKk3g8381FtCn0sxPEmA= X-Received: by 2002:a2e:5d57:: with SMTP id r84-v6mr21399879ljb.125.1525570277286; Sat, 05 May 2018 18:31:17 -0700 (PDT) MIME-Version: 1.0 Received: by 2002:a19:df46:0:0:0:0:0 with HTTP; Sat, 5 May 2018 18:31:16 -0700 (PDT) In-Reply-To: References: <95c5ed34fcb8394f33e67ac6f65a3cce@mail.kylheku.com> From: Anthony Green Date: Sun, 06 May 2018 01:31:00 -0000 Message-ID: Subject: Re: libffi trunk: new regressions on x86_64-linux-gnu, some test failures left on i686-linux-gnu To: "Kaz Kylheku (libffi)" <382-725-6798@kylheku.com> Cc: Matthias Klose , libffi-discuss@sourceware.org, "H.J. Lu" Content-Type: text/plain; charset="UTF-8" X-IsSubscribed: yes X-SW-Source: 2018/txt/msg00032.txt.bz2 That was the wrong report.. here's the right one: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85667 AG On Sat, May 5, 2018 at 9:30 PM, Anthony Green wrote: > On Sat, May 5, 2018 at 10:36 AM, Kaz Kylheku (libffi) < > 382-725-6798@kylheku.com> wrote: > >> On 2018-05-05 06:51, Anthony Green wrote: >> >>> These failures are showing up because we're testing the microsoft ABI >>> now. >>> >>> This looks like a bug in GCC. It's not returning small structures with >>> floating point values in the right registers when following the Microsoft >>> ABI. I'm going to figure out how to 'xfail' those tests and open a bug >>> against GCC. Clang appears to get it right. >>> >> >> When would this be an actual issue? >> > > As far as I know this is the first time this bug has been reported. I've > filed it here: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=43869 > > GCC is internally consistant, but can't generate code that will interface > correctly to binaries built with clang or visual c. > > Since nobody has reported this problem before, I'm OK with having libffi > follow the correct ABI as long as the GCC hackers agree to fix this in > future versions of GCC. Libffi won't work with GCC-compiled ms_abi > functions returning short structs (8 bytes or less) containing floating > point values (a pretty narrow use-case!). This is why I'll just xfail > the problematic test cases when we know we're using GCC. > > AG > >