Bump spdlog to 1.11, add fmt as dependency for spdlog

[kkraus14]

Description

Bumps spdlog to 1.11.0 and adds fmt as a dependency of spdlog and sets the SPDLOG_FMT_EXTERNAL_HO cmake option for spdlog. Happy to change that to be controlled by an argument to the rapids_cpm_spdlog function if desired. I believe the existing testing should cover the changes made here as the spdlog and rmm related tests were failing until adding fmt to the spdlog BUILD_EXPORT_SET and INSTALL_EXPORT_SET.

Checklist

• I am familiar with the Contributing Guidelines.
• New or existing tests cover these changes.
• The documentation is up to date with these changes.
• The cmake-format.json is up to date with these changes.
• I have added new files under rapids-cmake/
  • I have added include guards (include_guard(GLOBAL))
  • I have added the associated docs/ rst file and update the api.rst

[rapids-bot]

Pull requests from external contributors require approval from a rapidsai organization member with write or admin permissions before CI can begin.

[bdice]

/ok to test

[bdice]

Requesting changes for now with two small comments. I am going to wait to merge this until I can babysit the RMM PR through to completion, to minimize potential downtime / downstream breakage. Probably next Monday.

[bdice]

/ok to test

[kkraus14]

This doesn't seem to be working properly in the case where spdlog and fmt aren't installed already locally when trying to build RMM:

CMake Error in CMakeLists.txt:
  export called with target "rmm" which requires target "fmt-header-only"
  that is not in this export set, but in multiple other export sets:
  /home/keith/git/rmm/build/_deps/fmt-build/fmt-targets.cmake,
  /home/keith/git/rmm/build/fmt-targets.cmake.

  An exported target cannot depend upon another target which is exported
  multiple times.  Consider consolidating the exports of the
  "fmt-header-only" target to a single export.

I think this is because we're depending on both spdlog and fmt and we transitively export fmt when exporting spdlog which causes fmt to be double exported? I would assume the solution to this is to pass on the export arguments into the rapids_cpm_fmt call in the rapids_cpm_spdlog call conditionally, but I'm not quite sure. @robertmaynard maybe you have an idea?

[robertmaynard]

I think this is because we're depending on both spdlog and fmt and we transitively export fmt when exporting spdlog which causes fmt to be double exported? I would assume the solution to this is to pass on the export arguments into the rapids_cpm_fmt call in the rapids_cpm_spdlog call conditionally, but I'm not quite sure. @robertmaynard maybe you have an idea?

We are doing multiple exports of the fmt package since it is also doing a call to export(. The correct approach it to remove our export in get_fmt ( https://github.com/rapidsai/rmm/pull/1177/files#r1104528086 ).

[robertmaynard]

/merge

Resolved