Directly implement native exception raise methods in miri #3319
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I was confused by the context here, since it's unclear what issue you are fixing, and what "old custom ABI" is. After reading the PR code and mulling over this for a bit, I think "old custom ABI" is the |
My bad. I was indeed referring to |
tests/pass/panic/unwind_dwarf.rs
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Maybe set this to something else since we're testing the unwinder mechanism in general, not specifically Rust panics?
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For miri_start_panic we have some interesting tests: miri_bad_start_panic, unwind_panic_abort. We probably want to have similar tests for this as well. Other than that, LGTM. |
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@bjorn3 what is the status of this? This seems basically done, just needs more tests. |
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☔ The latest upstream changes (presumably #3557) made this pull request unmergeable. Please resolve the merge conflicts. |
Windows still needs the old custom ABI as SEH unwinding isn't supported by miri. Unlike DWARF unwinding it preserves all stack frames until right after the do_catch function has executed. Because of this panic_unwind stack allocates the exception object. Miri can't currently model unwinding without destroying stack frames and as such will report a use-after-free of the exception object.
- share implementation with miri_starting_unwind - make test use a custom unwinding class - extend comments - use NeedsUnwind more consistently
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I did a bit of refactoring to finish the PR. Thanks for the initial idea! |
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☀️ Test successful - checks-actions |
This implements the
_Unwind_RaiseExceptionfunction used on pretty much every unix system for starting unwinding. This allows removing the miri special case from libpanic_unwind for unix.Windows still needs
miri_start_unwindas SEH unwinding isn't supported by miri. Unlike DWARF unwinding, SEH preserves all stack frames until right after the do_catch function has executed. Because of this panic_unwind stack allocates the exception object. Miri can't currently model unwinding without destroying stack frames and as such will report a use-after-free of the exception object.