[Bug libstdc++/56482] missing -lpthread in configure when checking for pthreads_num_processors_np

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56482



--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> 2013-02-28 
14:27:48 UTC ---

The function is only used in src/c++11/thread.cc which will already be linked

to libpthread.so if needed.