[Core] Fix spdlog build issue

[peytondmurray]

Why are these changes needed?

Currently an issue with spdlog is preventing Ray from compiling. This PR fixes that issue.

I'm not very familiar with spdlog, but as I understand it spdlog contains a bundled (vendored in) version of the fmt library which it uses to write output. I noticed the bazel build file for spdlog included fmt/*.h and fmt/bundled/*.h. I'm not sure what the difference between the two is here, but when building only using the bundled version of fmt, I'm able to compile successfully. I'd be grateful for someone more familiar with this part of the code base to comment (@vitsai ?)

Related issue number

Closes #35200.

Checks

• I've signed off every commit(by using the -s flag, i.e., git commit -s) in this PR.
• I've run scripts/format.sh to lint the changes in this PR.
• I've included any doc changes needed for https://docs.ray.io/en/master/.
  • I've added any new APIs to the API Reference. For example, if I added a
    method in Tune, I've added it in doc/source/tune/api/ under the
    corresponding .rst file.
• I've made sure the tests are passing. Note that there might be a few flaky tests, see the recent failures at https://flakey-tests.ray.io/
• Testing Strategy
  • Unit tests
  • Release tests
  • This PR is not tested :(

[peytondmurray]

@vitsai I'm able to build Ray just fine with this modification locally. Do you have any insight as to why spdlog fails to build on CI?

[xieus]

@vitsai Could you review this PR as requested? Thanks.

[vitsai]

It looks like this change breaks the arm64 build. What platform are you seeing build errors on?

[peytondmurray]

Indeed it does break the arm64 build, so this approach doesn't quite seem like the right solution. Here's my platform info:

$ uname -rms
Linux 6.3.3-arch1-1 x86_64

[vitsai]

Closing this for now, we can continue discussion on the issue thread.