[MIR] libclc

[Maarten Lankhorst]

Availability:
- Already in universe and available on applicable archs.

Rationale:
- Allows enabling support for OpenCL in mesa.

Security:
- No files installed suid, sgid.
- No binaries installed in sbin.
- Not a plugin to security sensitive software.
- Not a daemon or opening a sensitive port.

Quality assurance:
- Should work without configuration.
- No debconf questions.
- No long-term outstanding bugs and updates by debian.

 The status of important bugs in Debian's, Ubuntu's, and upstream's bug tracking systems must be evaluated. Links to these bug trackers need to be provided in the MIR report. Important bugs must be pointed out and discussed in the MIR report.
https://bugs.debian.org/cgi-bin/pkgreport.cgi?ordering=normal;archive=0;src=libclc;dist=unstable;repeatmerged=0 - No open bugs found.
1 bug found in ubuntu's bug tracker. Likely a user error because with manual bug verification it's shown that the bug is invalid.
Package is used for nvidia and r600 opencl support.
Testsuite cannot run, it requires the proprietary nvidia drivers.
debian/watch is empty, but explained in debian/watch why.

UI standards:
Not applicable.

Dependencies:
clang is in universe, but the clang source package llvm is in main.

Standards compliance:
Should meet standard, no lintian overrides or warnings.

Maintenance:
Simple package, low maintenance effort, and maintained well in Debian.

Background information:
Required to enable opencl support in mesa. Mesa will need clang too, so the added deps will be needed.

[Michael Terry (mterry)]

Looks mostly fine. But it doesn't re-build on current vivid?

/usr/lib/llvm-3.6/bin/llvm-as: ./generic/lib/shared/vload_impl.ll:124:6: error: unexpected type in metadata definition
!1 = metadata !{metadata !"char", metadata !5}
     ^
Makefile:244: recipe for target 'nvptx--nvidiacl/lib/shared/vload_impl.ll.bc' failed

Besides that, the metapackage "clang" will have to be promoted to main too. But that should be simple, its llvm-defaults source package is in main already, as is clang-3.6. Which makes me wonder, is it best practices to specify a clang version in your build-depends, or should it be left as just "clang"?

[Timo Aaltonen (tjaalton)]

builds fine with llvm-3.5 but not our default which is 3.6, probably needs updates to libclc..

[Oibaf (oibaf)]

Xenial has an updated libclc, synced with the current Debian package and built with llvm 3.7. What is still missing here? Moving libclc from universe to main?

[Matthias Klose (doko)]

llvm3.7 doesn't build on all architectures. please ensure that it builds with llvm3.8 (currently only in -proposed). but llvm3.6 should be fine ok for now, if it will build with 3.8.

[LocutusOfBorg (costamagnagianfranco)]

I don't see llvm3.8 in proposed.

[Oibaf (oibaf)]

llvm 3.7 now builds fine on all architectures, libclc can be moved to main with no changes.

[LocutusOfBorg (costamagnagianfranco)]

I would appreciate to wait a little bit, I asked to Sylvestre (the Debian Developer and Maintainer of llvm) an ack about my changes.

Please hold on.

[LocutusOfBorg (costamagnagianfranco)]

The fixed llvm is on proposed

[Michael Terry (mterry)]

llvm-3.7 is not our default in xenial yet. So either libclc should be switched to use 3.6 or our default should be updated to 3.7.

Also, looks like clang isn't technically in main yet. It's source package (llvm-toolchain-3.6) is. But it hasn't been promoted yet. I'd have to go see if that was just because we didn't need to yet or if there was a problem with it.

[Oibaf (oibaf)]

llvm 3.8 is in xenial proposed and builds fine everywhere now.

[Matthias Klose (doko)]

from my point of view having a c++ compiler in main which currently does not support the new libstdc++ ABI is not wanted. Could you investigate to build using g++? At least there is a configure option --with-cxx-compiler

[Timo Aaltonen (tjaalton)]

libclc builds fine with llvm-3.8, is that sufficient?

[Michael Terry (mterry)]

No, llvm-3.8 doesn't help here. I'm trying to avoid xenial having two llvms in main. Right now our default, supported llvm is llvm-3.6. So either we switch libclc to use our supported version, or we switch our supported version to be the one libclc uses.

[Timo Aaltonen (tjaalton)]

We've decided (separately) on 3.8 as the default in 16.04.

And libclc doesn't build with g++, needs clang.

[Michael Terry (mterry)]

OK, so we need to both update to llvm-3.8 in xenial and switch libclc to llvm-3.8.

I'll assign this MIR to doko, because he understands the intricacies of the toolkits better than me.

[Oibaf (oibaf)]

Any news? Today is xenial feature freeze.

[Timo Aaltonen (tjaalton)]

no, clang is not going to main before it supports the same libstdc++ ABI as g++