From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by sourceware.org (Postfix) with ESMTP id 831AB3858D35 for ; Mon, 11 Oct 2021 19:48:22 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 831AB3858D35 Received: from mail-ua1-f72.google.com (mail-ua1-f72.google.com [209.85.222.72]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-224-LIdti6r8M3a0QLR-fber0w-1; Mon, 11 Oct 2021 15:48:17 -0400 X-MC-Unique: LIdti6r8M3a0QLR-fber0w-1 Received: by mail-ua1-f72.google.com with SMTP id m40-20020ab05a6b000000b002c9d69624b0so8227984uad.1 for ; Mon, 11 Oct 2021 12:48:17 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=EIRuEBCY0bGmKDdtgKBrWVyiCMyKOV134u8GxTTT7Go=; b=B8Bz5bglceuIa4KMDxeeOo/rrcWF/BlqKBvhmMcGrDJltb+hoSLV251SU6wgFhJ/bQ 8P4H7VMDEs4p0G2eKZArnkd5mFudHmIuhgHo6F+lOGu7KWPo6AWalhLjdivCSyPQ6ubc gRR3OzG4Z0vW6yQaN1nFk93WbAJTeKZRIXzwvTEeL48fr32+Xy1STeq9kNPi1F5O2Js1 UaqJU+THn5W6QXTkPXrWN+jDbrL4LP9QDdV9dv58jRDRwJOHW9KZodFqYvTA/6PjzulV ghWqJoiqADcvlx4of9g9hk+hMIVO6NSAOhaoolqkCWs+TTIE6BjtNfUT/rHB5TvaqduZ 8HBA== X-Gm-Message-State: AOAM5333m8mJZieFucHpSZj2wahoXIr3pwZrsQznpxCnFBO2ziXdeM2M r/b5ul3JqY0M8HXeJDCfx0QGVpKSuq0rNWj1sw62Hw6wsWqQ7THjtd842HEyU/wk50sehc5V1RQ yROv2AHIfbYF7tBmSqILF6yjy3JnzgYPkOw== X-Received: by 2002:ab0:1447:: with SMTP id c7mr2240306uae.2.1633981696762; Mon, 11 Oct 2021 12:48:16 -0700 (PDT) X-Google-Smtp-Source: ABdhPJywxc6LbxZtLMsXYSpM5LqYr/SxiwcOIx5B0LK1wgZarKnvRhyrI3Aa5teNUarNXqp8B9p3pvUCLGGaxUjxn34= X-Received: by 2002:ab0:1447:: with SMTP id c7mr2240267uae.2.1633981696420; Mon, 11 Oct 2021 12:48:16 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Jonathan Wakely Date: Mon, 11 Oct 2021 20:48:05 +0100 Message-ID: Subject: Re: [PATCH] libstdc++: Fix compare_three_way for constexpr and Clang To: Paul Keir Cc: "gcc-patches@gcc.gnu.org" , "libstdc++@gcc.gnu.org" X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-6.4 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, KAM_SHORT, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=unavailable autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 11 Oct 2021 19:48:23 -0000 On Fri, 20 Aug 2021 at 21:19, Paul Keir wrote: > > Hi, > > The current compare_three_way implementation makes provision for constant= evaluation contexts (avoiding reinterpret_cast etc.), but the approach fai= ls with Clang; when it compares two const volatile void pointers: "comparis= on between unequal pointers to void has unspecified result". I include a fi= x and test. > > Could someone commit the attached patch for me? Sorry for dropping the ball on this again. I've applied the patch locally and I'm testing it now. Unless I'm mistaken, you do not have a copyright assignment on file with the FSF, is that right? Are you able to certify that you have the right to submit this to GCC, as described at https://gcc.gnu.org/dco.html ? Also, if GCC is failing to diagnose the invalid comparisons here then that should be reported to bugzilla as a c++ "accepts-invalid" bug.