http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46455
--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> 2010-11-12 20:25:19 UTC --- What's the value of __gnu_cxx::__default_lock_policy on Mingw? Is it the same for GCC 4.4 and 4.5? Between 4.4 and 4.5 there are some changes to the ghtr-win32.h file which provides the gthreads abstraction layer, but there are no significant changes to shared_ptr. So for the moment I think it's either a change in the atomic operations supported by mingw or a change in the threading layer, not shared_ptr
