From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from simark.ca (simark.ca [158.69.221.121]) by sourceware.org (Postfix) with ESMTPS id F3EFC3870909 for ; Sat, 30 May 2020 16:02:49 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org F3EFC3870909 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=simark.ca Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=simark@simark.ca Received: from [10.0.0.11] (173-246-6-90.qc.cable.ebox.net [173.246.6.90]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by simark.ca (Postfix) with ESMTPSA id 660C61E791; Sat, 30 May 2020 12:02:49 -0400 (EDT) Subject: Re: [PATCHv2 3/7] hurd: make function cast stronger To: gdb-patches@sourceware.org, Thomas Schwinge , thomas@schwinge.name, bug-hurd@gnu.org References: <20200529220049.gm7vt7gvtw7if6lg@function> <20200529220153.63gej54cam7itzmk@function> <20200530153213.fcl5cqeescdqs6xv@function> From: Simon Marchi Message-ID: Date: Sat, 30 May 2020 12:02:49 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.1 MIME-Version: 1.0 In-Reply-To: <20200530153213.fcl5cqeescdqs6xv@function> Content-Type: text/plain; charset=utf-8 Content-Language: fr Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-4.8 required=5.0 tests=BAYES_00, KAM_DMARC_STATUS, SPF_HELO_PASS, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 30 May 2020 16:02:51 -0000 On 2020-05-30 11:32 a.m., Samuel Thibault wrote: > Simon Marchi, le sam. 30 mai 2020 10:47:50 -0400, a ecrit: >> On 2020-05-29 6:01 p.m., Samuel Thibault wrote: >>> process_reply_S.c:104:23: error: function called through a non-compatible type [-Werror] >>> 104 | OutP->RetCode = (*(kern_return_t (*)(mach_port_t, kern_return_t)) S_proc_setmsgport_reply) (In0P->Head.msgh_request_port, In0P- >>> >>> gdb/ChangeLog: >>> >>> 2020-05-29 Samuel Thibault >>> >>> * reply_mig_hack.awk (Error return): Cast function through >>> void *, to bypass compiler function call check. >> >> If you are silencing a compiler warning, please explain why it is safe to do so. > > It is not actually safe, as explained by the comment above the changed > lines, but as explained by the comment above really fixing it is very > far from trivial. > > In my repo I have added > > “ > As the existing comment says, it is in general not safe to drop some parameters > like this, but this is the error handling case, where the called function does > not actually read them, and mig is currently planned to be used on i386 and > x86_64 only, where this is not a problem. As the existing comment says, fixing > it properly would be far from trivial: we can't just pass 0 for them, as they > might not be scalar. > ” > > Is that enough of an explanation for the changelog? Ok, thanks, I missed that comment. But yeah, I think that text for the commit message (not ChangeLog entry) is helpful! Simon