your changes http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=149531 and
broke the build of pthreads for windows.
The patch for w64 has to be adopted.
Thank you for telling this. I sent already an new patch to pthread's ML (which fixes additional things for x64), and this shouldn't have those failures. The fix on gcc's trunk is necessary, as it the _X86_ define has not to be on x86_64 target (just for i?86 builds). Sadly we noticed this pretty late, so I'll take a look to the patch and will correct it as far as necessary.