http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51827
--- Comment #2 from Dmitry Gorbachev <d.g.gorbachev at gmail dot com> 2012-01-12 10:53:44 UTC --- I already mentioned "PCH" and ".H" extension, but just to be 100% clear, the error happens only when compiling the testcase as a c++ header. Reproduced on i686-pc-linux-gnu and i686-pc-mingw32.