From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 42480 invoked by alias); 25 Sep 2017 16:06:17 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 42469 invoked by uid 89); 25 Sep 2017 16:06:16 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-0.9 required=5.0 tests=BAYES_00,KAM_LAZY_DOMAIN_SECURITY,RP_MATCHES_RCVD,SPF_HELO_PASS autolearn=no version=3.3.2 spammy=nuances, inappropriate, Hx-languages-length:1395, filed X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Mon, 25 Sep 2017 16:06:14 +0000 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 32AE5C057FA7; Mon, 25 Sep 2017 16:06:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 32AE5C057FA7 Authentication-Results: ext-mx08.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx08.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=palves@redhat.com Received: from [127.0.0.1] (ovpn04.gateway.prod.ext.ams2.redhat.com [10.39.146.4]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3BD7070BDB; Mon, 25 Sep 2017 16:06:12 +0000 (UTC) Subject: Re: [pushed] microblaze-tdep: Add ATTRIBUTE_PRINTF to microblaze_debug To: Michael Eager , Simon Marchi , gdb-patches@sourceware.org References: <1505995878-10687-1-git-send-email-simon.marchi@ericsson.com> <078ea0b6-71aa-f74d-33fc-859322d4668a@eagerm.com> From: Pedro Alves Message-ID: <441bab33-67b9-be36-e4b7-c22e6936a7bf@redhat.com> Date: Mon, 25 Sep 2017 16:06:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <078ea0b6-71aa-f74d-33fc-859322d4668a@eagerm.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-SW-Source: 2017-09/txt/msg00756.txt.bz2 On 09/25/2017 03:14 PM, Michael Eager wrote: > On 09/21/2017 05:11 AM, Simon Marchi wrote: >> I am getting this warning with clang: >> >> /home/emaisin/src/binutils-gdb/gdb/microblaze-tdep.c:94:28: error: >> format string is not a string literal [-Werror,-Wformat-nonliteral] >> vprintf_unfiltered (fmt, args); >> ^~~ >> >> Adding ATTRIBUTE_PRINTF to microblaze_debug gets rid of it. Strangely, >> > gcc doesn't warn about non-literal format strings when calling vprintf >> (or a vprintf-style function, like vprintf_unfiltered). I filed this >> gcc bug: >> >> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82206 > > I'll admit to not being familiar with the nuances of __attribute__ > ((format ...)), > or why adding this to the function declaration of microblaze_debug() > would suppress > a diagnostic on the call to vprintf_unfiltered(), Because with that the compiler can assume that the 'fmt' argument as passed down to microblaze_debug is a string literal. I.e., the compiler can tell that the argument to vprintf_unfiltered is itself transitively a string literal. > but the better fix > seems to me to > be to turn off the obviously inappropriate -Wformat-nonliteral option in > microblaze_debug() using > #pragma GCC diagnostic ignored "-Wformat-nonliteral" That doesn't make sense to me. Thanks, Pedro Alves