[Bug libstdc++/51026] Bootstrap failure due to libstdc++ on x86_64-darwin11

[fxcoudert at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51026

--- Comment #1 from Francois-Xavier Coudert <fxcoudert at gcc dot gnu.org> 2011-11-08 08:06:07 UTC ---
Should have added: this is with trunk revision , and probably due to

2011-11-07  Andrew MacLeod  <amacleod@redhat.com>

        * include/bits/atomic_base.h (atomic_thread_fence): Revert.
        (atomic_signal_fence): Revert.

2011-11-07  Andrew MacLeod  <amacleod@redhat.com>

        * include/bits/atomic_base.h (atomic_thread_fence): Call builtin.
        (atomic_signal_fence): Call builtin.
        (atomic_flag::test_and_set): Call __atomic_exchange when it is
lockfree,
        otherwise fall back to call __sync_lock_test_and_set.
        (atomic_flag::clear): Call __atomic_store when it is lockfree,
        otherwise fall back to call __sync_lock_release.