what's the plan for mac os x lion

[Jack Howarth]

On Mon, Jul 04, 2011 at 01:29:31PM -0700, Blair Zajac wrote:
> 
> On Jul 4, 2011, at 11:30 AM, Jack Howarth wrote:
> 
> > On Mon, Jul 04, 2011 at 11:16:48AM -0700, Blair Zajac wrote:
> >> On Jul 4, 2011, at 11:14 AM, Jeremy Huddleston wrote:
> >>> 
> >>> All of the ports that are in my install-set (including many multimedia 
> >>> ports, x11, firefox, gnome, with most bloat variants set) have been 
> >>> working with trunk/base using llvm-gcc-4.2 on SL and Lion for a while 
> >>> now (trunk/base now chooses the compiler based on devtools version 
> >>> rather than os version).  I'm still holding on to a couple NDA-squimish 
> >>> patches in leaf projects that I'll push after the actual release, but 
> >>> it mostly works out of the box.
> >>> 
> >>> If you are uncertain if filing your bug would violate your NDA, please 
> >>> feel free to email me directly.
> >> 
> >> Out of curiosity, Apple hasn't bumped to a newer gcc version?  Does  
> >> anybody know why?  Did they stick with 4.2 for compatibility for  
> >> libstdc++?
> >> 
> >> Blair
> > 
> >   If Apple had access to clang in its current state at the start of Lion's
> > development, I'm sure we would have had clang as the default compiler but
> > alas they have no time machines. FYI, I rewrote fink to implement a prefix-path-clang
> > that defaults fink to use clang for cc/gcc and clang++ for cxx/g++ as the default
> > compilers for package builds under 10.7. So far we have had few problems with using
> > clang as the default compiler under fink 10.7. The FreeBSD folks have been
> > building with clang for awhile now...
> > 
> > http://wiki.freebsd.org/BuildingFreeBSDWithClang
> > http://wiki.freebsd.org/PortsAndClang
> > http://rainbow-runner.nl/clang/patches/
> > 
> > and is another resource for clang specific patches.
> >              Jack
> 
> Thanks Jack.
> 
> How's the performance of clang versus gcc 4.2?

  A quick and dirty benchmark with himenoBMTxpa.c at -O3 -ffast-math shows...

Apple gcc-4.2      MFLOPS measured : 171.335360
Apple clang        MFLOPS measured : 186.050091
clang svn          MFLOPS measured : 230.703334
FSF gcc 4.6.1      MFLOPS measured : 249.262880
FSF gcc 4.7svn     MFLOPS measured : 255.698154

Hopefully by the time clang becomes the system compiler, clang/llvm will have caught up
with FSF gcc in terms of vectorization support.
         Jack


> 
> Blair