Break out of the correct number of scopes in loops #62388
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We were incorrectly breaking out of one too many drop scopes when generating MIR for loops and breakable blocks, resulting in use after free and associated borrow checker warnings. This wasn't noticed because the scope that we're breaking out of twice is only used for temporaries that are created for adjustments applied to the loop. Since loops generally propagate coercions to the `break` expressions, the only case we see this is when the type of the loop is a smart pointer to a trait object.
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…tion, r=eddyb Break out of the correct number of scopes in loops We were incorrectly breaking out of one too many drop scopes when generating MIR for loops and breakable blocks, resulting in use after free and associated borrow checker warnings. This wasn't noticed because the scope that we're breaking out of twice is only used for temporaries that are created for adjustments applied to the loop. Since loops generally propagate coercions to the `break` expressions, the only case we see this is when the type of the loop is a smart pointer to a trait object. Closes rust-lang#62312
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Rollup of 10 pull requests Successful merges: - #62123 ( Remove needless lifetimes (std)) - #62150 (Implement mem::{zeroed,uninitialized} in terms of MaybeUninit.) - #62169 (Derive which queries to save using the proc macro) - #62238 (Fix code block information icon position) - #62292 (Move `async || ...` closures into `#![feature(async_closure)]`) - #62323 (Clarify unaligned fields in ptr::{read,write}_unaligned) - #62324 (Reduce reliance on `await!(...)` macro) - #62371 (Add tracking issue for Box::into_pin) - #62383 (Improve error span for async type inference error) - #62388 (Break out of the correct number of scopes in loops) Failed merges: r? @ghost
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We were incorrectly breaking out of one too many drop scopes when
generating MIR for loops and breakable blocks, resulting in use after
free and associated borrow checker warnings.
This wasn't noticed because the scope that we're breaking out of twice
is only used for temporaries that are created for adjustments applied to
the loop. Since loops generally propagate coercions to the
breakexpressions, the only case we see this is when the type of the loop is a
smart pointer to a trait object.
Closes #62312