Apple will use LLVM

[Jakub Jelinek]

On Wed, Feb 22, 2012 at 08:46:19AM +0100, Roman Rakus wrote:
> On 02/16/2012 05:33 PM, Jakub Jelinek wrote:
> >For just -O3 or -O2 -ftree-vectorize we could perhaps have some knob in
> >the spec files to request those extra flags, for PGO it really requires
> >some work from the packager (but e.g. bash/grep/awk, perhaps perl/python
> >etc. would definitely improve, gcc itself is already built with PGO).
> 
> What kind of work? I have tried to build bash with added -O2
> -ftree-vectorize -fprofile-generate, but the build fails with many
> undefined reference to `__gcov_*.

That would be probably because -lgcov isn't linked in.  When using
-fprofile-generate, you need to pass that switch not just during
compilation, but also when linking the binaries (or libraries) that contain
-fprofile-generate compiled objects.

	Jakub