Telcon: 2022 04 06

Attendees

• Peter Scheibel (host)
• Mark Krentel
• Massimiliano Culpo
• Tammy Dahlgren
• Nick Sly
• Phil Regier
• Wileam Phan
• Greg Becker
• Brian Van Essen

Agenda items

• Possibly continue from https://github.com/spack/spack/wiki/Telcon%3A-2022-03-09: Packages with multiple build systems

  • https://github.com/spack/spack/pull/29530
  • (Peter) What about external package repositories

• (Wileam) Request a warning directive https://spackpm.slack.com/archives/C5VL7V81G/p1648838405907499, which can be used like:

warning(when='%nvhpc', msg='NVHPC compiler is not well tested for this package')

• This would be a directive and the associated message would be printed as part of concretization vs. installation

• (Peter) How is this significantly different from conflicts?

  • It allows the concretization to complete (whereas conflicts stop it from happening)
  • (Mark) For hpctoolkit, it was intended to work with GNU compilers, but we don't want to explicitly prohibit using e.g. the %intel compiler

• Regarding the desire to "reject any compiler except %gcc", is there support for "not" in Spec syntax?

  • Currently no
  • Instead of allowing when=!x, could there be an except=x?
  • Instead of conflicts(), could there be requires() as in requires(%gcc)
    • See: https://github.com/spack/spack/pull/21765
    • This would be useful in particular for constraining multi-valued dependencies (which would be hard to do with conflicts)
  • requires by itself would have trouble supporting a use case like "I need either %intel or %gcc"
    • https://github.com/spack/spack/pull/27987 would help with that
  • (Massimiliano) Are there any use cases that don't involve a compiler?
    • Once compilers-as-dependencies is implemented, there generally won't be a need
    • (Mark) an example of a use case requesting "or"/"not" that doesn't concern compilers: a package that is intended for x86 (32 or 64 bit)
  • So far here we've discussed supporting this with directives (which seems the most straightforward)
    • Supporting "!spec" as part of when could also work but is uncertain
    • like when="!(%gcc or %intel)"

• (Wileam) AOCC 3.2.0 can't compile Python https://spackpm.slack.com/archives/C01AQUZA6Q5/p1648498167258169 https://github.com/spack/spack/issues/29115

  • This might need to be resolved by the Python/AOCC developers
  • Sometimes users submit a patch to Spack (although if that patch is needed to build the package, it is often preferable to submit that to the Package code itself and then restrict the Package to build with the updated version)

Agenda items for next week

• Continue from https://github.com/spack/spack/wiki/Telcon%3A-2022-03-30: vendored CUDA dependencies
• go-bootstrap build failure on aarch64 (not darwin, which we already have a conflict for)

Possible Agenda items

• (Wileam) Can't bootstrap llvm@13 and @14 if gold is enabled (which is the default behavior) https://github.com/spack/spack/issues/29350
• How to reorganize the docs?