[compiler-rt] [sanitizer-common] Improve mach_vm_region_recurse error handling (PR #158670)

[Dan Blackwell via llvm-commits]

https://github.com/DanBlackwell approved this pull request.

I'm happy with this now. I agree with @wrotki that the address walk feels 'tricky', but I think it's a tricky problem - I'm happy to stick with the current implementation, but let's wait for @wrotki final opinion.

https://github.com/llvm/llvm-project/pull/158670