re PR c++/13684 (local static object variable constructed once but ctors and dtors called multiple times on same memory when called in multiple threads)
PR c++/13684
* cp/decl.c (expand_static_init): Use thread-safety API.
(register_dtor_fn): Return the call, don't expand it.
* cp/tree.c (add_stmt_to_compound): New fn.
(stabilize_call): Use it.
* gimplify.c (gimplify_cleanup_point_expr): Handle CLEANUP_EH_ONLY.
(gimple_push_cleanup): Add eh_only parm.
(gimplify_target_expr): Pass it.
* c.opt (-fno-threadsafe-statics): New option.
* c-opts.c (c_common_handle_option): Handle it.
* c-common.h (flag_threadsafe_statics): Declare it.
* c-common.c (flag_threadsafe_statics): Record it.
* doc/invoke.texi: Document it.
* tsystem.h (_GNU_SOURCE): Define.
* gthr-posix.h (__gthread_recursive_mutex_t): New typedef.
(__GTHREAD_RECURSIVE_MUTEX_INIT): New macro.
(__GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION): New macro.
(__gthread_recursive_mutex_init_function): New fn.
(__gthread_recursive_mutex_lock): New fn.
(__gthread_recursive_mutex_trylock): New fn.
(__gthread_recursive_mutex_unlock): New fn.
* gthr-solaris.h, gthr-single.h, gthr-dce.h: Likewise.
* gthr-win32.h, gthr-vxworks.h: Likewise.
* gthr.h: Document.
* libsupc++/guard.cc (static_mutex): Internal class implementing a
recursive mutex which controls initialization of local statics.
(__gnu_cxx::recursive_init): New exception class.
(__cxa_guard_acquire): Deal with locking and recursion detection.
(acquire_1, __cxa_guard_abort, __cxa_guard_release): Likewise.
From-SVN: r86687
