From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 123403 invoked by alias); 31 Mar 2016 00:45:58 -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 123391 invoked by uid 89); 31 Mar 2016 00:45:57 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.4 required=5.0 tests=AWL,BAYES_00,FREEMAIL_FROM,RCVD_IN_DNSWL_LOW,SPF_PASS autolearn=ham version=3.3.2 spammy= X-HELO: mail-ig0-f175.google.com Received: from mail-ig0-f175.google.com (HELO mail-ig0-f175.google.com) (209.85.213.175) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES128-GCM-SHA256 encrypted) ESMTPS; Thu, 31 Mar 2016 00:45:56 +0000 Received: by mail-ig0-f175.google.com with SMTP id nk17so115435423igb.1 for ; Wed, 30 Mar 2016 17:45:56 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc; bh=yB9uxB+W10Btq6Oov1rKKpr1sorBnR3+R/r2Mz9D+i8=; b=NCywxgcyHEO7OhY9x0/Y8yoHCLpfUM88j6traGkNxYYAjlCKqIhNtF28b3umO4uNfC NgkHtsDtoWdTaFDS7Efrv8g8WrquD9Gwqc5afphuCceb7EgXn9GngwonL4CnSlb44Uu1 B0P5CEw2Vg/xWrDo+g4VaT0AwXqFq0oKkmcSq+1ZABvAi3ra5h8aATZDXK/4XZ8sZsDm Vn+Ng7wykk0WChZTwzejjybq81Xzo6ux7MITT/ew/XnVG/RTFTC39y3LssYSnfnSzytk cqpBnwhfH604Dg0QQaLX5cMNrIbScZj2LzNADdzjn2EPXKrCzcBnYe79NZNwpWl9evIy aZ7Q== X-Gm-Message-State: AD7BkJJdrXVMlysBvJLsi3wX4S7/CXJ3jYHCA1OQ+NufxuI3j44aCARaIktf/D2YA4uw17WJL3n0lkjj7VPvVw== MIME-Version: 1.0 X-Received: by 10.50.112.71 with SMTP id io7mr12488825igb.50.1459385154456; Wed, 30 Mar 2016 17:45:54 -0700 (PDT) Received: by 10.36.200.8 with HTTP; Wed, 30 Mar 2016 17:45:54 -0700 (PDT) In-Reply-To: <20160330143421.GM15812@bubble.grove.modra.org> References: <983472E1-A1BC-4970-9CF9-0138A6BAD16D@apple.com> <6AAD87D2-90F9-4AD7-A195-AC91B76EA6AE@apple.com> <56FB5061.9010303@redhat.com> <20160330143421.GM15812@bubble.grove.modra.org> Date: Thu, 31 Mar 2016 00:45:00 -0000 Message-ID: Subject: Re: Preventing preemption of 'protected' symbols in GNU ld 2.26 From: Cary Coutant To: Alan Modra Cc: Jeff Law , "H.J. Lu" , Joe Groff , Binutils Content-Type: text/plain; charset=UTF-8 X-IsSubscribed: yes X-SW-Source: 2016-03/txt/msg00445.txt.bz2 > 2) Emit dynamic text relocations for non-PIC executable access to > protected visibility variables defined in shared libraries. Makes > executable pages with text relocations non-shared between processes. > (But can be shared again after relocation if two processes have the > same layout.) Note that this is not always possible, depending on the addressing range of the code emitted. For example, a pc-relative access may have sufficient range to reach a variable copied into the executable's bss, but not sufficient range to reach the original definition in a shared library. -cary