std: don't clean up the main thread's altstack - #161037
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| // Store a pointer to the allocation for the main thread's altstack so that | ||
| // tools like valgrind don't complain about a leaked unreachable allocation. | ||
| // | ||
| // If the main thread exits, the process will terminate so there's no use in | ||
| // freeing resources. It also means that the altstack is still installed | ||
| // while TLS destructors are run on the main thread (c.f. #111272). |
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Minor nit: since we can generate private docs these should probably just be doc comments.
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Agree with the discussion that this is probably a lot more headaches than it's worth, although I think it's probably worth verifying that we've fixed the issues with flushing output on exit. It looks like that code has been since relocated, but I'm not 100% sure just looking at it. |
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Fixes #161018
#28069 added a call to what is now
rt::cleanuptoprocess::exit.rt::cleanupin turn calls the UNIXstack_overflow::cleanup, which frees the main thread's signal stack and uninstalls the current thread's signal handler in the assumption that the current thread is the main one – even thoughprocess::exitcan be called from any thread.This PR removes the main thread cleanup logic altogether, since, as the FIXME in
stack_overflow::cleanuppoints out, it causes more issues than it is worth. This also means that stack overflows in TLS destructors will be caught on the main thread, partly addressing #111272.