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Be more careful with type of left operand of <<

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On a 32-bit system, evaluating 1<<31 causes undefined behaviour because
1 is signed and so it produces signed overflow.  UBSan has spotted a
couple of occasions where this happens in Puzzles, so in each case I've
converted the left operand to the unsigned result type we actually want.
This commit is contained in:
Ben Harris
2023-02-26 14:24:38 +00:00
parent 9dbcfa765b
commit 93be3f7cca
2 changed files with 4 additions and 4 deletions
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4
cube.c
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@ -202,8 +202,8 @@ struct game_grid {
};
#define SET_SQUARE(state, i, val) \
((state)->bluemask[(i)/32] &= ~(1 << ((i)%32)), \
(state)->bluemask[(i)/32] |= ((!!val) << ((i)%32)))
((state)->bluemask[(i)/32] &= ~(1UL << ((i)%32)), \
(state)->bluemask[(i)/32] |= ((unsigned long)(!!val) << ((i)%32)))
#define GET_SQUARE(state, i) \
(((state)->bluemask[(i)/32] >> ((i)%32)) & 1)