Challenge 10: Kani contracts for String memory safety - #645
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both ubuntu jobs die with a runner shutdown signal shortly after string::verify::check_from_utf16le_lossy starts, while the 3-thread macos jobs finish that same harness in 238s, so it was peaking the 16 gb runner's memory rather than failing a check. switched it to kissat, the same remedy core::ptr uses for check_align_offset_5; state space and check count are unchanged. |
Add safety contracts and proof harnesses covering String allocation and mutation. Runtime stdlib logic is unchanged: everything added here is either a contract attribute or lives behind cfg(kani). check_from_utf16le_lossy runs under the kissat solver. On a little-endian target that harness keeps the align_to::<u16> arms of from_utf16le_lossy live, two of which go through from_utf16_lossy with symbolic RawVec growth, and the resulting solve peaks the memory of the 16 GB ubuntu runner while the same harness completes on macOS. Selecting kissat follows the existing precedent for check_align_offset_5 in core::ptr and leaves the state space and check count unchanged. Fixes rust-lang#61
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Summary
Kani safety contracts and proof harnesses for this challenge. Runtime stdlib logic is unchanged; annotations are cfg(kani) / contract attributes.
String allocation/mutation safety contracts.
Validation
challenge/10-stringscripts/run-kani.sh)Fixes #61
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