From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 9307 invoked by alias); 5 Feb 2012 23:53:48 -0000 Received: (qmail 9292 invoked by uid 22791); 5 Feb 2012 23:53:47 -0000 X-SWARE-Spam-Status: No, hits=-1.8 required=5.0 tests=AWL,BAYES_00,TW_FN,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from bromo.med.uc.edu (HELO bromo.med.uc.edu) (129.137.3.146) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Sun, 05 Feb 2012 23:53:31 +0000 Received: from bromo.med.uc.edu (localhost.localdomain [127.0.0.1]) by bromo.med.uc.edu (Postfix) with ESMTP id 2D349400009; Sun, 5 Feb 2012 18:53:28 -0500 (EST) Received: (from howarth@localhost) by bromo.med.uc.edu (8.14.3/8.14.3/Submit) id q15NrR5w009545; Sun, 5 Feb 2012 18:53:27 -0500 Date: Sun, 05 Feb 2012 23:53:00 -0000 From: Jack Howarth To: Jonathan Wakely Cc: gcc-patches , Rainer Orth Subject: Re: Gthreads patch to disable static initializer macros Message-ID: <20120205235327.GA9528@bromo.med.uc.edu> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org X-SW-Source: 2012-02/txt/msg00215.txt.bz2 On Sun, Feb 05, 2012 at 08:26:22PM +0000, Jonathan Wakely wrote: > PRs libstdc++/51296 and libstdc++/51906 are both caused by problems > with the Pthreads static initializer macros such as > PTHREAD_MUTEX_INITIALIZER. > > On Tru64 PTHREAD_MUTEX_INITIALIZER and PTHREAD_COND_INITIALIZER can > only be used for statically-initialized variables, as allowed by POSIX > currently, but http://austingroupbugs.net/view.php?id=70#c127 removes > that limitation for the next POSIX standard. C++11 needs to use those > macros for variables with automatic and dynamic scope, because the > init functions can't be used in constexpr constructors. > > On Mac OS X 10.7 the PTHREAD_RECURSIVE_MUTEX_INITIALIZER is buggy. > This has shown up now because C++11 threads weren't enabled on darwin > before 4.7 > > My suggestion is to modify gthr-posix.h with the attached patch, so > that target maintainers can define e.g. > _GTHREAD_USE_RECURSIVE_MUTEX_INIT_FUNC to force use of the init > function instead of the __GTHREAD_RECURSIVE_MUTEX_INIT initializer. > The patch includes a change to do that for darwin. > > This has been testing on darwin, if Rainer tests it successfully on > Tru64 will the gthr-posix.h change be acceptable? There are no unexpected libstdc++ testsuite regressions on x86_64-apple-darwin11 with this patch applied to current gcc trunk. > diff --git a/libgcc/gthr-posix.h b/libgcc/gthr-posix.h > index 46054f6..45b15a8 100644 > --- a/libgcc/gthr-posix.h > +++ b/libgcc/gthr-posix.h > @@ -74,6 +74,20 @@ typedef struct timespec __gthread_time_t; > #define __GTHREAD_COND_INIT PTHREAD_COND_INITIALIZER > #define __GTHREAD_TIME_INIT {0,0} > > +#ifdef _GTHREAD_USE_MUTEX_INIT_FUNC > +# undef __GTHREAD_MUTEX_INIT > +# define __GTHREAD_MUTEX_INIT_FUNCTION __gthread_mutex_init_function > +#endif > +#ifdef _GTHREAD_USE_RECURSIVE_MUTEX_INIT_FUNC > +# undef __GTHREAD_RECURSIVE_MUTEX_INIT > +# undef __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION > +# define __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION __gthread_recursive_mutex_init_function > +#endif > +#ifdef _GTHREAD_USE_COND_INIT_FUNC > +# undef __GTHREAD_COND_INIT > +# define __GTHREAD_COND_INIT_FUNCTION __gthread_cond_init_function > +#endif > + > #if SUPPORTS_WEAK && GTHREAD_USE_WEAK > # ifndef __gthrw_pragma > # define __gthrw_pragma(pragma) > @@ -730,6 +744,15 @@ __gthread_setspecific (__gthread_key_t __key, const void *__ptr) > return __gthrw_(pthread_setspecific) (__key, __ptr); > } > > +#ifdef _GTHREAD_USE_MUTEX_INIT_FUNC > +static inline void > +__gthread_mutex_init_function (__gthread_mutex_t *__mutex) > +{ > + if (__gthread_active_p ()) > + __gthrw_(pthread_mutex_init) (__mutex, NULL); > +} > +#endif > + > static inline int > __gthread_mutex_destroy (__gthread_mutex_t *__mutex) > { > @@ -778,7 +801,8 @@ __gthread_mutex_unlock (__gthread_mutex_t *__mutex) > return 0; > } > > -#ifndef PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP > +#if !defined( PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP) \ > + || defined(_GTHREAD_USE_RECURSIVE_MUTEX_INIT_FUNC) > static inline int > __gthread_recursive_mutex_init_function (__gthread_recursive_mutex_t *__mutex) > { > @@ -828,6 +852,15 @@ __gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *__mutex) > return __gthread_mutex_unlock (__mutex); > } > > +#ifdef _GTHREAD_USE_COND_INIT_FUNC > +static inline void > +__gthread_cond_init_function (__gthread_cond_t *__cond) > +{ > + if (__gthread_active_p ()) > + __gthrw_(pthread_cond_init) (__cond, NULL); > +} > +#endif > + > static inline int > __gthread_cond_broadcast (__gthread_cond_t *__cond) > { > diff --git a/libstdc++-v3/config/os/bsd/darwin/os_defines.h b/libstdc++-v3/config/os/bsd/darwin/os_defines.h > index ccefeaf..421478d 100644 > --- a/libstdc++-v3/config/os/bsd/darwin/os_defines.h > +++ b/libstdc++-v3/config/os/bsd/darwin/os_defines.h > @@ -39,4 +39,7 @@ > // -flat_namespace to work around the way that it doesn't. > #define _GLIBCXX_WEAK_DEFINITION __attribute__ ((weak)) > > +// Static initializer macro is buggy in darwin, see libstdc++/51906 > +#define _GTHREAD_USE_RECURSIVE_MUTEX_INIT_FUNC > + > #endif