[Mesa-dev] [RFC PATCH 00/16] A new IR for Mesa

[Michel Dänzer]

On 21.08.2014 03:56, Matt Turner wrote:
> On Wed, Aug 20, 2014 at 11:13 AM, Kenneth Graunke <kenneth at whitecape.org> wrote:
>> Gentoo has also had trouble updating for similar reasons; Matt (the Gentoo Mesa package mantainer) can probably comment more.
> 
> Yes, at one point we were stuck two releases behind current Mesa (and
> this is Gentoo!) because we couldn't get the appropriate version of
> LLVM stabilized because a number of reverse dependencies didn't work
> with the new LLVM version.
> 
> Having multiple versions installed in parallel breaks down pretty
> easily. Where do the headers go? Where do all the executables go? Do
> you version all of them and install one for each version?

Yes.

> Do other distros allow multiple versions of LLVM to be installed in parallel?

Yes.

> How do they manage?

In Debian (and presumably Ubuntu), there are llvm-3.*-* packages for
each major version, which contain everything in
/usr/{include,lib,share}/llvm-3.* and then there are meta-packages such
as llvm-dev which provide links for the default version in
/usr/{bin,include}.

AFAICT this only requires a few small patches for the LLVM/clang build.
I might have missed something related in one of the other patches though.


-- 
Earthling Michel Dänzer            |                  http://www.amd.com
Libre software enthusiast          |                Mesa and X developer