[libcxx-commits] [libcxx] [libc++] Ensure that `std::expected` has no tail padding (PR #69673)

[Louis Dionne via libcxx-commits]

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In-Reply-To: <llvm.org/llvm/llvm-project/pull/69673 at github.com>


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

I have a few comments but this looks good to me. It would be amazing if @huixie90 could also have one last look since we spent so much time discussing this patch in our 1:1s for the past few months.

@jiixyj I want to thank you for taking the lead on this important fix. This has been one of the trickiest bugs (and fix) I've ever seen in the library and you stepped up with a comprehensive fix and diligent testing. Please know that this provides great value to the project and that the quality of this contribution is recognized and appreciated.

In terms of next steps, please address remaining comments (which are nitpicks), and then I'll "squash and merge" this on Friday after my 1:1 with @huixie90, or earlier if Hui has time to have a final look. I'll then handle the communication with vendors and summarize the state of things (for both this and `__movable_box`) in #70820 , but that's easy since we have release notes.

https://github.com/llvm/llvm-project/pull/69673