Fix provenance-ABA in lockless queues using fuzzy provenance

[joboet]

This is a hot-fix for #121950 which solves the described problem using fuzzy provenance. Better solutions exist, but they require LLVM support and a lot more effort.

CC @RalfJung

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[RalfJung]

Thanks for looking into this!

Unfortunately this will mean everyone using Miri on macOS will get warnings about the int2ptr casts in every program (since these types are using in pre-main code). That's also why CI fails.

I think ideally we'd find a solution where exposed provenance is only used with codegen, but Miri can track the proper provenance with the new CAS intrinsic we discussed. That doesn't require LLVM changes. It's still a lot more work, but I don't think this issue is particularly high priority.

[Mark-Simulacrum]

I'm going to go ahead and close per @RalfJung's comment -- I don't think exposing lots of warnings is a good idea.