http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53197
--- Comment #13 from H.J. Lu <hjl.tools at gmail dot com> 2012-05-03 00:02:26 UTC --- Created attachment 27294 --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27294 auto-host.h on Fedora/15/x86-64 Here is auto-host.h on Fedora/15/x86-64. How does it compare against yours?