Makes zigzag encoding and decoding save wrt. undefined behavior, see #28 #35
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daniel-j-h
commented
Jul 5, 2021
| @@ -2,7 +2,7 @@ | |||
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| static inline | |||
| uint32_t _zigzag_encode_32 (int32_t val) { | |||
| return (val + val) ^ (val >> 31); | |||
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The signed val + val here is the issue wrt. overflow causing undefined behavior
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Please see PR #36 |
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Closing in favour of #36 |
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This changes the zigzag encoding and decoding implementation so that we never run into undefined behavior with signed integer overflows. See thread starting at #28 (comment) cc @lemire