[compiler-rt] [sanitizer-common] Ensure at least sizeof(void*) alignment in sanitizer allocator (PR #84440)

[Alexander Richardson via llvm-commits]

arichardson wrote:

> This change seems reasonable to me. If you want to rebase on latest and ensure tests are happy I can merge it

Thanks for the review - I will rebase and merge this tomorrow.

https://github.com/llvm/llvm-project/pull/84440