Cooking LLVM in FreeBSD 8

[Geoff Fritz]

On Tue, Mar 17, 2009 at 01:49:24PM +0100, Wojciech Puchar wrote:
> > On Ivoras'FreeBSD page, ``What's cooking for FreeBSD 8''
> >
> > http://ivoras.sharanet.org/freebsd/freebsd8.html
> 
> LLVM site shows it's something like precompiler+runtime compiling.
> 
> will it be used that way, or as usual compiler?

I think the idea is to get away from gcc with its evil GPL3 license as the
default compiler.  To that end, it looks like decent strides are being
made with the clang front end to llvm:

http://wiki.freebsd.org/BuildingFreeBSDWithClang

I got bored one day and installed the port, set CC=ccc in /etc/make.conf
then built a few ports with it to benchmark against various gcc incantations.
(Very unscientific, so I won't post numbers).

I wasn't quite bored enough to try a make world with it, though.  But 
according the the link I provide, it appears to be 99% of the way there.

As best I can tell, there would be a non-trvial performance loss with using
clang at this point.  At wth least with the version that's currently in the
ports tree (I didn't try building from the latest svn version).

It does look promising, though.  I hope it'll eventually surpass gcc in
optimization of code.  I'm sure others are anxious for license purity within
the base system.

-- Geoff