On 13/10/16 07:14 PM, Emil Velikov wrote: > On 13 October 2016 at 04:07, Michel Dänzer <mic...@daenzer.net> wrote: >> On 13/10/16 03:37 AM, Tobias Droste wrote: >>> Am Mittwoch, 12. Oktober 2016, 11:53:50 CEST schrieb Emil Velikov: >>>>> >>>>> +LLVM_VERSION_REQUIRED_OPENCL=3.6.0 >>>>> +LLVM_VERSION_REQUIRED_R600=3.6.0 >>>>> +LLVM_VERSION_REQUIRED_RADEONSI=3.6.0 >>>> >>>> There's a small related gotcha: as-is at build time we get the >>>> different codepaths thus, as people build against shared LLVM (hello >>>> Archlinux, I'm looking at you) and update their LLVM without >>>> rebuilding mesa (Arch I'm looking at you again) things go funny. >> >> What exactly happened there? LLVM upstream generates shared libraries >> named libLLVM-<major>.<minor>.so*, so it shouldn't be possible for a >> simple LLVM package update to break Mesa, unless Arch did something >> really stupid. >> > The issue is not specific to Arch, but anyone who links against shared LLVM. > > Here is another take on it: > At least swr and r600/radeonsi depend at _build_ time on the _patch_ > version of LLVM. The latter of which is not part of the DSO name. Thus > at runtime as you change your LLVM (3.9.x>3.9.y) you'll execute the > "3.9.x" codepath even though you are be using "3.9.y" LLVM.
That should be fine, since 3.9.y is backwards compatible with 3.9.x. Debian doesn't automatically recompile Mesa in such cases either, and I haven't seen any problems there because of that. So, what exactly was the problem? >>>> Tl;Dr; We really want to enable static linking by default and prod >>>> distros to use it. >>> >>> I'm all in favor of statically linking LLVM (that's the way I'm doing this >>> on >>> my pc). >>> I think the only reason this is not done is because people (also here on the >>> list) don't want any static linkg of external libraries because of size or >>> whatever. >>> So changing the default to static is easy, but I doubt it will make everyone >>> happy ;-) >> >> Indeed, it'd probably make many distro packagers unhappy, because >> they'll just have to re-enable shared linking, because packaging >> policies generally strongly discourage if not outright forbid static >> linking. >> > The toggle is there and is not going away, afaict. If people are going > to get upset that the default does not meet their policy... just > toggle and get on with other things ;-) The question is if it makes sense for the default to be different from what the majority of users end up using. It doesn't to me. -- Earthling Michel Dänzer | http://www.amd.com Libre software enthusiast | Mesa and X developer _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
