thread name in stack overflow message
Fixesrust-lang/rust#144481, which is caused by the thread name not being initialised yet when setting up the stack overflow information. Unfortunately, the stack overflow UI test did not test for the correct thread name being present, and testing this separately didn't occur to me when writing https://github.com/rust-lang/rust/pull/140628.
This PR contains the smallest possible fix I could think of: passing the thread name explicitly to the platform thread creation function. In the future I'd very much like to explore some possibilities around merging the thread packet and thread handle into one structure and using that in the platform code instead – but that's best left for another PR.
This PR also amends the stack overflow test to check for thread names, so we don't run into this again.
``@rustbot`` label +beta-nominated
4bfbd80bab