Type-check Yul assignment arity against builtin return count#425
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Yul builtins/opcodes either return a single value or none at all (when typed as `unit`). The Yul type checker previously accepted `let x := mstore(1, 1)` and similar assignments even though `mstore` does not produce a value. Compare the number of names on the left-hand side of `YAssign`/`YLet` with the actual arity of the right-hand side and report a type error on mismatch.
rodrigogribeiro
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Jun 2, 2026
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Looks good! Great work!
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Claude is pretty good! 😅 |
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Yul builtins/opcodes either return a single value or none at all (when typed as
unit). The Yul type checker previously acceptedlet x := mstore(1, 1)and similar assignments even thoughmstoredoes not produce a value. Compare the number of names on the left-hand side ofYAssign/YLetwith the actual arity of the right-hand side and report a type error on mismatch.Fixes #383.
Disclaimer: Mostly created by Claude.