[Bug libstdc++/71684] Memory leak with std::mutex and std::lock_guard on freebsd

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71684

--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Jonathan Wakely from comment #3)
> On some older versions of FreeBSD using PTHREAD_MUTEX_INITIALIZER and then
> pthread_mutex_destroy would segfault, see
> http://lists.freebsd.org/pipermail/freebsd-threads/2010-September/004905.html

I misremembered, it aborts. Still not good though.