[Mesa-dev] [PATCH] configure.ac: fix the --disable-llvm-shared-libs build

[Michel Dänzer]

On 20.04.2016 22:10, Jose Fonseca wrote:
> On 19/04/16 19:39, Emil Velikov wrote:
>> On 19 April 2016 at 15:47, Chuck Atkins <chuck.atkins at kitware.com> wrote:
>>> This still doesn't quite give what you want.  One can also have an
>>> llvm with
>>> component shared libs.  So there's three different options for llvm
>>> library
>>> configurations: a single shared lib, component shared libs, or component
>>> static libs.
>>  From the three - only single shared lib and component static libs are
>> supported.
>>
>> Personally I'm leaning that we ought to go with the latter only... Esp
>> considering the problems that people tend to have with mesa + steam,
>> every so often.
>>
>> IIRC all the issues that we had with static llvm have been resolved.
>> Plus we have great people like Kai who promptly send patches when
>> things break (which hasn't happen in a long time)
>>
>> Tom, what is your view on the topic - are you ok with us switching
>> back to static one and/or nuking the shared one ? Iirc Jose was clear
>> that in his view one should just static link LLVM. I believe that's
>> still the case, right Jose ?
> 
> Yes, I think that distros should statically link LLVM.  Otherwise Mesa's
> LLVM can clash with other projects LLVM, which can and often do require
> a different LLVM version.  And there's *lots* of projects out there that
> use LLVM and OpenGL, particularly languages w/ JIT compilation.

FWIW, that sort of thing can work with shared LLVM with current versions
of LLVM which use versioned symbols. I tested the gambas OpenGL support
with gambas and radeonsi linked against different versions of LLVM a
while ago, worked fine. (I also confirmed that it breaks with older
versions of LLVM which didn't use versioned symbols)

There may be other cases which still break even with versioned symbols
though.


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