http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51885
--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> 2012-01-20 19:31:48 UTC --- (In reply to comment #4) > i am quite sure there is something strange : reinterpret_cast is used to cast > a > float pointer to a uint32_t pointer > > these two types have the same size (4 bytes) > > therefore, the swap function (following the reinterpret_cast) should work > properly ... No, the C++ standard says your code has undefined behaviour. Please read the section "Casting does not work as expected when optimization is turned on" at http://gcc.gnu.org/bugs/#nonbugs_c and the article it links to, http://mail-index.netbsd.org/tech-kern/2003/08/11/0001.html
