*: fix overflow in comparator functions used by sorted containers (backport #22498) - #22574
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Several comparator functions registered with DECLARE_SKIPLIST_NONUNIQ, DECLARE_RBTREE_UNIQ, and RB_GENERATE use unsigned integer subtraction to produce a comparison result. When the difference between two uint32_t values exceeds INT_MAX, the subtraction wraps around in unsigned arithmetic and the resulting value, when interpreted as a signed int, can have the wrong sign. This causes incorrect ordering in skip-lists and red-black trees. The fix replaces `return a - b` with explicit greater-than/less-than comparisons that always produce the correct sign. Signed-off-by: anlan_cs <vic.lan@pica8.com> (cherry picked from commit f36824e)
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Several comparator functions registered with DECLARE_SKIPLIST_NONUNIQ, DECLARE_RBTREE_UNIQ, and RB_GENERATE use unsigned integer subtraction to produce a comparison result. When the difference between two uint32_t values exceeds INT_MAX, the subtraction wraps around in unsigned arithmetic and the resulting value, when interpreted as a signed int, can have the wrong sign. This causes incorrect ordering in skip-lists and red-black trees.
The fix replaces
return a - bwith explicit greater-than/less-than comparisons that always produce the correct sign.This is an automatic backport of pull request #22498 done by Mergify.