From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 19581 invoked by alias); 10 Jul 2012 19:07:40 -0000 Received: (qmail 19569 invoked by uid 22791); 10 Jul 2012 19:07:39 -0000 X-SWARE-Spam-Status: No, hits=-4.3 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00,KHOP_THREADED X-Spam-Check-By: sourceware.org Received: from localhost (HELO gcc.gnu.org) (127.0.0.1) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Tue, 10 Jul 2012 19:07:27 +0000 From: "naesten at gmail dot com" To: gcc-bugs@gcc.gnu.org Subject: [Bug preprocessor/53920] "gcc -E" does not honor #pragma GCC diagnostic ignored "-Wunused-macro" Date: Tue, 10 Jul 2012 19:07:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: preprocessor X-Bugzilla-Keywords: diagnostic X-Bugzilla-Severity: normal X-Bugzilla-Who: naesten at gmail dot com X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated Content-Type: text/plain; charset="UTF-8" MIME-Version: 1.0 Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org X-SW-Source: 2012-07/txt/msg00866.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53920 --- Comment #1 from Samuel Bronson 2012-07-10 19:07:26 UTC --- Oh, I suppose I should mention that I ran into this because I was using ccache to compile Emacs with --enable-gcc-warnings, and by default ccache runs the preprocessor and the compiler in separate passes (so that it can skip the compilation proper if it has cached output for a given preprocessor output), and then pastes together the diagnostic output from the two passes. (Thankfully, setting the environment variable CCACHE_CPP2 causes ccache to throw out the preprocessor output after hashing, which is a quite effective workaround for this sort of thing, though preprocessing the source twice does make things a bit slower on cache misses.)