http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55145
--- Comment #7 from H.J. Lu <hjl.tools at gmail dot com> 2012-11-04 22:51:46 UTC --- Here are different internal values from the same input: 32-bit long: 1.57079632679489661925640447970309310221637133509 Input: 1.5707963267948966192021943710788178805159986950457096099853515625 64-bit long: 1.57079632679489661914798426245454265881562605500221252441 Input value is extremely close to a half-way value between 32-bit and 64-bit longs.