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r?@joshtriplett

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Miri usesmiri_start_panic as unwind entrypoint, which is called by panic_unwind's__rust_start_panic, so no miri changes needed afaict.

For reference, my previous comment was "I think this will require changes to Miri". I deleted it shortly after posting it, as I realized it was incorrect :)

This looks like a nice improvement. Maybe squish the commits though?

Rebased and squashed.

@bors r+ rollup

📌 Commitb874502 has been approved byChrisDenton

It is now in thequeue for this repository.

🌲 The tree is currentlyclosed for pull requests below priority 100. This pull request will be tested once the tree is reopened.