------- Comment #12 from rguenther at suse dot de 2009-04-25 14:29 ------- Subject: Re: gcc-4.4 -Wstrict-aliasing and -Wstrict-aliasing=3 behaves like -Wstrict-aliasing=2 in gcc-4.3
On Sat, 25 Apr 2009, pinskia at gmail dot com wrote: > ------- Comment #10 from pinskia at gmail dot com 2009-04-25 14:25 ------- > Subject: Re: gcc-4.4 -Wstrict-aliasing and > -Wstrict-aliasing=3 behaves like -Wstrict-aliasing=2 in gcc-4.3 > > On Sat, Apr 25, 2009 at 7:22 AM, edwintorok at gmail dot com > <gcc-bugzi...@gcc.gnu.org> wrote: > > > Hmm, looks like the only way out is for me to put #if defined(__GNUC__) && > > (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4) and use memcpy. > > Either that or add a configure rule to add -fno-strict-aliasing. > > GCC has been able to optimize memcpy since at least 3.0.0 so using: > #if (__GNUC__ >=3) > > Should be good enough (undefined macros are substituted with 0 in #if's). Not on the tree level though. At least 4.3 doesn't optimize it there which may indeed pessimize optimization. Richard. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39895
