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 8AB05385C426 for ; Mon, 1 Jun 2020 02:05:47 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 8AB05385C426 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)) (No client certificate requested) by simark.ca (Postfix) with ESMTPSA id 046C61E072; Sun, 31 May 2020 22:05:45 -0400 (EDT) Subject: Re: [PATCH] hurd: Add shared mig declarations To: gdb-patches@sourceware.org, Thomas Schwinge , thomas@schwinge.name, bug-hurd@gnu.org References: <20200530182318.hh3k7uuhvhfrqo5g@function> <3ec177fc-e9b6-42a0-0aa9-3cec13e9a577@simark.ca> <20200531072032.hfegxapkqv3a3hrb@function> From: Simon Marchi Message-ID: <5bbcce80-bd49-9903-0825-2235c73880e3@simark.ca> Date: Sun, 31 May 2020 22:05:45 -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: <20200531072032.hfegxapkqv3a3hrb@function> Content-Type: text/plain; charset=utf-8 Content-Language: fr Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-4.7 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: Mon, 01 Jun 2020 02:05:48 -0000 On 2020-05-31 3:20 a.m., Samuel Thibault wrote: > Simon Marchi, le sam. 30 mai 2020 21:51:35 -0400, a ecrit: >> On 2020-05-30 2:23 p.m., Samuel Thibault wrote: >>> Fixes >>> >>> exc_request_S.c:177:24: error: no previous declaration for ‘exc_server’ [-Werror=missing-declarations] >>> 177 | mig_external boolean_t exc_server >>> >>> gdb/ChangeLog: >>> >>> * config/i386/i386gnu.mn [%_S.o %_U.o] (COMPILE.post): Add >>> "-include gnu-nat-mig.h". >>> * gnu-nat-mig.h: New file. >>> * gnu-nat.c: Include "gnu-nat-mig.h". >>> (exc_server, msg_reply_server, notify_server, >>> process_reply_server): Remove declarations. >> >> It took me a while to understand the underlying problem. My understanding is that >> gnu-nat.c calls this function exc_server, that is defined in the generated file. The >> generated file does not provide a header with declarations, so gnu-nat.c had its own >> local declaration. Since we now use the -Wmissing-declarations warning flag, and the >> definition in the generated exc_request_S.c didn't see a corresponding declaration, >> it caused that build failure. Is that correct? If so, please add that explanation >> or equivalent to the commit log. > > I have now added > > “ > We are using -Werror=missing-declarations, and the _S.h files generated > by mig do not currently include a declaration for the server routine. > gnu-nat.c used to have its own external declarations, but better just > share them between gnu-nat.c and the _S.c files. > ” Thanks, that sounds good. And this way, I suppose that if for some reason the prototypes don't match, we'll get a compilation error (which is a good thing). >> My question now is: that MIG tool appears to generate both a header (%_S.h) and source >> file (%_S.c) from defs files. What is this header file used for, if it doesn't contain >> the declaration for the functions in the source file? > > Mig does include declarations for the functions of the .c files, but > not for the server routine, I don't know why that was never implemented > there (this hasn't been touched since the VCS initial import). Ok. Simon