gthr-posix.h (__gthread_cond_broadcast, [...]): Add to extend interface for POSIX conditional variables.

2007-09-13  Doug Kwan  <dougkwan@google.com>

        * gcc/gthr-posix.h (__gthread_cond_broadcast, __gthread_cond_wait,
        __gthread_cond_wait_recursive): Add to extend interface for POSIX
        conditional variables. (__GTHREAD_HAS_COND): Macro defined to signify
        support of conditional variables.
        * gcc/gthr-posix95.h (__gthread_cond_broadcast, __gthread_cond_wait,
        __gthread_cond_wait_recursive): Add to extend interface for POSIX
        conditional variables. (__GTHREAD_HAS_COND): Macro defined to signify
        support of conditional variables.
        * gcc/gthr-single.h (__gthread_cond_broadcast, __gthread_cond_wait,
        __gthread_cond_wait_recursive): Add to extend interface for POSIX
        conditional variables.
        * gcc/gthr.h: Update comments to document new interface.
        * libstdc++-v3/include/ext/concurrent.h (class __mutex,
        class __recursive_mutex): Add new method gthread_mutex to access
        inner gthread mutex.
        [__GTHREAD_HAS_COND] (class __concurrence_broadcast_error,
        class __concurrence_wait_error, class __cond): Add.
        * guard.cc (recursive_push, recursive_pop): Delete.
        (init_in_progress_flag, set_init_in_progress_flag): Add to
        replace recursive_push and recursive_pop.
        (throw_recursive_init_exception): Add.
        (acquire, __cxa_guard_acquire, __cxa_guard_abort and
        __cxa_guard_release): [__GTHREAD_HAS_COND] Use a conditional
        for synchronization of static variable initialization.
        The global mutex is only held briefly when guards are
        accessed. [!__GTHREAD_HAS_COND] Fall back to the old code,
        which deadlocks.
        * testsuite/thread/guard.cc: Add new test. It deadlocks with the
        old locking code in libstdc++-v3/libsup++/guard.cc.

From-SVN: r129030

1 files changed, 18 insertions, 0 deletions

diff --git a/gcc/gthr.h b/gcc/gthr.h
index b9d1641..a37b911 100644
--- a/gcc/gthr.h
+++ b/gcc/gthr.h
@@ -81,6 +81,24 @@ Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
      int __gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex);
      int __gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex);
 
+   The following are supported in POSIX threads only. They are required to
+   fix a deadlock in static initialization inside libsupc++. The header file
+   gthr-posix.h defines a symbol __GTHREAD_HAS_COND to signify that these extra
+   features are supported.
+
+   Types:
+     __gthread_cond_t
+
+   Macros:
+     __GTHREAD_COND_INIT
+     __GTHREAD_COND_INIT_FUNCTION
+
+   Interface:
+     int __gthread_cond_broadcast (__gthread_cond_t *cond);
+     int __gthread_cond_wait (__gthread_cond_t *cond, __gthread_mutex_t *mutex);
+     int __gthread_cond_wait_recursive (__gthread_cond_t *cond,
+					__gthread_recursive_mutex_t *mutex);
+
    All functions returning int should return zero on success or the error
    number.  If the operation is not supported, -1 is returned.