From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 11544 invoked by alias); 26 Mar 2014 19:29:05 -0000 Mailing-List: contact binutils-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: binutils-owner@sourceware.org Received: (qmail 11532 invoked by uid 89); 26 Mar 2014 19:29:05 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.5 required=5.0 tests=AWL,BAYES_00,FREEMAIL_FROM,RCVD_IN_DNSWL_LOW,SPF_PASS autolearn=ham version=3.3.2 X-HELO: mail-oa0-f42.google.com Received: from mail-oa0-f42.google.com (HELO mail-oa0-f42.google.com) (209.85.219.42) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES128-SHA encrypted) ESMTPS; Wed, 26 Mar 2014 19:29:03 +0000 Received: by mail-oa0-f42.google.com with SMTP id i4so3153582oah.1 for ; Wed, 26 Mar 2014 12:29:02 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.182.142.229 with SMTP id rz5mr64968491obb.12.1395862142045; Wed, 26 Mar 2014 12:29:02 -0700 (PDT) Received: by 10.76.151.198 with HTTP; Wed, 26 Mar 2014 12:29:01 -0700 (PDT) In-Reply-To: References: <20140325203952.GA11925@intel.com> <20140325223910.GJ18201@bubble.grove.modra.org> <20140325235256.GK18201@bubble.grove.modra.org> Date: Wed, 26 Mar 2014 19:29:00 -0000 Message-ID: Subject: Re: [PATCH] PR ld/16746: Don't issue a warning for reference in LTO IR From: "H.J. Lu" To: Binutils Content-Type: text/plain; charset=ISO-8859-1 X-IsSubscribed: yes X-SW-Source: 2014-03/txt/msg00276.txt.bz2 On Tue, Mar 25, 2014 at 5:41 PM, H.J. Lu wrote: > On Tue, Mar 25, 2014 at 4:52 PM, Alan Modra wrote: >> On Tue, Mar 25, 2014 at 03:50:05PM -0700, H.J. Lu wrote: >>> On Tue, Mar 25, 2014 at 3:39 PM, Alan Modra wrote: >>> > On Tue, Mar 25, 2014 at 01:39:52PM -0700, H.J. Lu wrote: >>> >> case WARNC: >>> >> - /* Issue a warning and cycle. */ >>> >> - if (h->u.i.warning != NULL) >>> >> + /* Issue a warning and cycle. Don't issue a warning for >>> >> + reference in LTO IR which may be removed by LTO later. */ >>> >> + if (h->u.i.warning != NULL >>> >> + && (abfd->flags & BFD_PLUGIN) == 0) >>> > >>> > So here you're handling references in LTO IR for warning symbols >>> > defined in real object files or other LTO IR files.. >>> >>> Yes. >>> >>> >> case WARN: >>> >> + /* Don't issue a warning for reference in LTO IR which may be >>> >> + removed by LTO later. Make a warning symbol instead. */ >>> >> + if ((hash_entry_bfd (h)->flags & BFD_PLUGIN) != 0) >>> >> + goto mwarn; >>> >> + >>> > >>> > And here you have the case where the new symbol is a warning symbol, >>> > in either LTO IR or real object files, but the reference was in an LTO >>> > IR file. >>> >>> Yes. >>> >>> > What about the CWARN case, where you already have a definition that >>> > may have been referenced, and the new symbol is a warning symbol? >>> > You'll need to test h->non_ir_ref I think. >>> >>> It is: >>> >>> https://sourceware.org/bugzilla/show_bug.cgi?id=12760 >> >> That's a different issue, isn't it? I'm talking about the sequence >> 1a) symbol referenced, >> 2a) symbol defined, >> 3a) warning symbol defined. >> or >> 1b) symbol defined, >> 2b) symbol referenced, >> 3b) warning symbol defined. >> >> If (1a) or (2b) is an IR reference then we don't want to warn. > > The symbol is referenced and used even if it has been inlined. > Testing h->non_ir_ref isn't sufficient. We also want to know > if it is used in LTO. > With the fix for PR 16756: https://sourceware.org/ml/binutils/2014-03/msg00275.html we won't issue warnings for (1a) or (2b) if they are either inlined or removed. -- H.J.