[OpenMP] avoid segv for a lock that has already been destroyed

[lfmeadow]

This can happen in static destructors when called after the
runtime is already shutdown (e.g., by ompt_finalize_tool). Even
though it is technically an error to call omp_destroy_lock after
shutdown, the application doesn't necessarily know that omp_destroy_lock
was already called. This is safe becaues all indirect locks are
destoryed in __kmp_cleanup_indirect_user_locks so the return
value will always be valid or a nullptr, not garbage.

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[lfmeadow]

@TerryLWilmarth @jpeyton52 could you please review this? I realize it is a point fix but it addresses a use case in RAJA and seems like a nice user-friendly thing to do. It shows up with AMD's rocprof-sdk which implements its own OMPT client tool.
I can easily add a lit test.

[TerryLWilmarth]

LGTM
@hansangbae Does this look okay to you too?

[hansangbae]

Looks fine to me.

[lfmeadow]

Can someone please approve the workflow?

[github-actions]

✅ With the latest revision this PR passed the C/C++ code formatter.

[jprotze]

Can you add a test case for this?

[lfmeadow]

Can you add a test case for this?

Will do.

[jprotze]

Thanks! Also, thanks for working on this and coming up with a fix! Some performance tool folks also complained to me about this before.

[lfmeadow]

Thanks! Also, thanks for working on this and coming up with a fix! Some performance tool folks also complained to me about this before.

You're welcome. Yes, it came from RAJA . There are probably some others lurking but this one seemed to be likely enough that it was worth a point fix.

[lfmeadow]

@jprotze OK, test is added and I fixed the formatting issue. I guess there's another workflow approval required.

[jprotze]

Lgtm