From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 89566 invoked by alias); 20 Apr 2016 17:45:23 -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 89036 invoked by uid 89); 20 Apr 2016 17:45:04 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.6 required=5.0 tests=BAYES_00,MISSING_HEADERS,RCVD_IN_DNSWL_LOW,RP_MATCHES_RCVD,SPF_PASS autolearn=ham version=3.3.2 spammy=insure, day!, H*r:sk:2016042, H*r:192.168.3 X-HELO: eastrmfepo203.cox.net Received: from eastrmfepo203.cox.net (HELO eastrmfepo203.cox.net) (68.230.241.218) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Wed, 20 Apr 2016 17:44:54 +0000 Received: from eastrmimpo110.cox.net ([68.230.241.223]) by eastrmfepo203.cox.net (InterMail vM.8.01.05.15 201-2260-151-145-20131218) with ESMTP id <20160420174452.HNVM11952.eastrmfepo203.cox.net@eastrmimpo110.cox.net> for ; Wed, 20 Apr 2016 13:44:52 -0400 Received: from [192.168.3.15] ([72.219.207.23]) by eastrmimpo110.cox.net with cox id khks1s00E0WpXgw01hksJn; Wed, 20 Apr 2016 13:44:52 -0400 X-CT-Class: Clean X-CT-Score: 0.00 X-CT-Spam: 0 X-Authority-Analysis: v=2.1 cv=Jtd/raIC c=1 sm=1 tr=0 a=mYpcIwsqoufCTD7dyaqayA==:117 a=mYpcIwsqoufCTD7dyaqayA==:17 a=L9H7d07YOLsA:10 a=9cW_t1CCXrUA:10 a=s5jvgZ67dGcA:10 a=IkcTkHD0fZMA:10 a=JTJ_G5Ydp3oEQRp1EhsA:9 a=QEXdDO2ut3YA:10 X-CM-Score: 0.00 Authentication-Results: cox.net; none Message-ID: <5717B8A5.4070905@cox.net> Date: Wed, 20 Apr 2016 17:45:00 -0000 From: anonymous User-Agent: Thunderbird 2.0.0.24 (X11/20100228) MIME-Version: 1.0 CC: Binutils , GCC Subject: Re: Preventing preemption of 'protected' symbols in GNU ld 2.26 [aka should we revert the fix for 65248] References: <6AAD87D2-90F9-4AD7-A195-AC91B76EA6AE@apple.com> <56FB5061.9010303@redhat.com> <20160330143421.GM15812@bubble.grove.modra.org> <571161D0.10601@redhat.com> <20160418144911.GG15088@bubble.grove.modra.org> <20160419050805.GI15088@bubble.grove.modra.org> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-IsSubscribed: yes X-SW-Source: 2016-04/txt/msg00341.txt.bz2 H.J. Lu wrote: > On Tue, Apr 19, 2016 at 7:06 AM, Michael Matz wrote: >> Hi, >> >> On Tue, 19 Apr 2016, Richard Biener wrote: >> >>> So with all this it sounds that current protected visibility is just >>> broken and we should forgo with it, making it equal to default >>> visibility? >> Like how? You mean in GCC regarding protected as default visibility? No, >> that's just throwing out the baby with the water. We should make >> protected do what it was intended to do and accept that not all invariants >> that are true for default visible symbols are also true for protected >> symbols, possibly by ... >> >>> At least I couldn't decipher a solution that solves all of the issues >>> with protected visibility apart from trying to error at link-time (or >>> runtime?) for the cases that are tricky (impossible?) to solve. > > Protected visibility is a useful feature. But as it stands today, > it is pretty much useless on x86 as seen in ld and ld.so. We > have known this defect for a long time, almost from day 1. To > make it truly useful, we need to clearly spell out how and when > it can be used. We should enforce its limitation in compiler, > ld and ld.so so that there is no surprise, either for correctness or > performance, at run-time. > > my prefference would be if you (re)add it: do so such that there is no portability issue with next or previous gcc version (or other cc if possible), and that it be left as optional with a quick note that it is, and insure both on and off both build w/o fail in doing so. picky? thank you, have a nice day!