rawhide report: 20050510 changes

[Jakub Jelinek]

On Tue, May 10, 2005 at 02:19:32PM +0200, Ralf Ertzinger wrote:
> On Tue, May 10, 2005 at 08:12:35AM -0400, Build System wrote:
> 
> > - on x86 and x86_64, use -msse and -msse2 to accomodate newer compilers
> 
> Not that I want to revive the whole .i386.rpm vs. i686.rpm discussion,
> but... how does gcc handle these flags? Does it build alternative
> code for processors that do not have these features? Or does the binary
> not run on anything below PII or compatible?

The way it is done in current rawhide's GIMP is definitely wrong.
%ifarch %ix86 x86_64
CFLAGS="%optflags -msse -msse2" CXXFLAGS="%optflags -msse -msse2" \
%endif
%configure \

a) on x86-64 this is unnecessary, all x86-64's have -msse2 by default
b) -msse2 implies -msse
c) if you use -msse2 in CFLAGS for all files, you can't run the latest
   GIMP on e.g. Pentium2, or pre-x86_64 AMD chips.
   -msse2 should be ONLY used on sources that have SSE/SSE2 stuff in it,
   and GIMP should make sure that no routine from those sources will be
   ever called on pre-SSE2 chips

	Jakub