From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 6222 invoked by alias); 27 Jun 2012 15:00:13 -0000 Received: (qmail 6179 invoked by uid 22791); 27 Jun 2012 15:00:09 -0000 X-SWARE-Spam-Status: No, hits=-3.0 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00 X-Spam-Check-By: sourceware.org Received: from localhost (HELO sourceware.org) (127.0.0.1) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 27 Jun 2012 14:59:56 +0000 From: "ajax at redhat dot com" To: glibc-bugs@sources.redhat.com Subject: [Bug nptl/14304] New: Provide some parts of librt in libc as well Date: Wed, 27 Jun 2012 15:00:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: glibc X-Bugzilla-Component: nptl X-Bugzilla-Keywords: X-Bugzilla-Severity: enhancement X-Bugzilla-Who: ajax at redhat dot com X-Bugzilla-Status: NEW X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: unassigned at sourceware dot org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Changed-Fields: Message-ID: X-Bugzilla-URL: http://sourceware.org/bugzilla/ Auto-Submitted: auto-generated Content-Type: text/plain; charset="UTF-8" MIME-Version: 1.0 Mailing-List: contact glibc-bugs-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: glibc-bugs-owner@sourceware.org X-SW-Source: 2012-06/txt/msg00287.txt.bz2 http://sourceware.org/bugzilla/show_bug.cgi?id=14304 Bug #: 14304 Summary: Provide some parts of librt in libc as well Product: glibc Version: 2.13 Status: NEW Severity: enhancement Priority: P2 Component: nptl AssignedTo: unassigned@sourceware.org ReportedBy: ajax@redhat.com CC: drepper.fsp@gmail.com Classification: Unclassified librt links against libpthread, mostly because aio_* are implemented in threads instead of in the kernel AFAICT. This is unfortunate, because many libraries would like to use (for example) clock_gettime, but doing so pulls in pthreads. Now you have no choice but to hit the more expensive thread-safe paths, because your library can't know whether multiple threads actually exist, only whether the pthread symbols are non-zero. The complementary problem also exists for applications that are unthreaded: if they link against librt, pthread symbols will be non-zero, and any thread-safe library beneath that app now has to behave thread-safely. This is especially comic when reading the clock_gettime implementation, which goes out of its way to work correctly regardless of whether __pthread_clock_gettime is available. Ideally it would be possible to provide most of these symbols from libc directly (presumably versioned so the app requires a sufficiently new libc). -- Configure bugmail: http://sourceware.org/bugzilla/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.