murmur2: fix undefined behaviour#42
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The Buffer struct held a MaybeUninit<[u8; 4]> which was written to byte-by-byte via assume_init_mut. The problem is that assume_init_mut requires the entire value is fully initialized. This fix changes Buffer.bytes to [MaybeUninit<u8>; 4], where each byte is its own MaybeUninit. Writes go through MaybeUninit::write() on individual elements which has no initialization requirement.
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CC @eldruin |
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If you're doing this can you add safety comments on every |
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Manishearth
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Apr 27, 2026
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Went ahead and did it myself in #43. But this PR looks good.
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The
Bufferstruct held aMaybeUninit<[u8; 4]>which was written to byte-by-byte viaassume_init_mut. The problem is thatassume_init_mutrequires the entire value is fully initialized.This fix changes
Buffer.bytesto[MaybeUninit<u8>; 4], where each byte is its ownMaybeUninit. Writes go throughMaybeUninit::write()on individual elements which has no initialization requirement.