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Sema: fix single-range switch prong capture #30793

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mlugg merged 1 commit from justusk/zig:switch-fix-single-range-capture into master 2026年01月11日 22:40:03 +01:00
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Follow-up to #30776

The comment on analyzeSwitchPayloadCapture was slightly wrong, if the switch prong contains ranges case_vals is also undefined, not just if is_special_prong is set! So using case_vals outside of blocks where it's known that there are no ranges might actually access undefined memory (even though you'd have to be pretty unlucky for case_vals.len to be exactly 1 instead of some other garbage value).

Follow-up to #30776 The comment on `analyzeSwitchPayloadCapture` was slightly wrong, if the switch prong contains ranges `case_vals` is also `undefined`, not just if `is_special_prong` is set! So using `case_vals` outside of blocks where it's known that there are no ranges might actually access `undefined` memory (even though you'd have to be pretty unlucky for `case_vals.len` to be exactly `1` instead of some other garbage value).
Sema: fix single-range switch prong capture
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e2338edb47 
This kind of capture cannot always be comptime-known, assuming so caused
access of undefined memory during payload capture analysis!
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Dammit, I thought we were good! 😛 Thanks for spotting this quickly!

Dammit, I thought we were good! 😛 Thanks for spotting this quickly!
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