\
BUG_ON(_i >= (h)->used); \
(h)->used--; \
- heap_swap(h, _i, (h)->used); \
- heap_sift_down(h, _i, cmp); \
- heap_sift(h, _i, cmp); \
+ if ((_i) < (h)->used) { \
+ heap_swap(h, _i, (h)->used); \
+ heap_sift_down(h, _i, cmp); \
+ heap_sift(h, _i, cmp); \
+ } \
} while (0)
#define heap_pop(h, d, cmp) \