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6a81cabc14
region_model.cc's tree_cmp attempted to verify that the ordering is symmetric by asserting that tree_cmp (x, y) == -tree_cmp (y, x) This condition is too strong: it's only required for a comparator that sign (tree_cmp (x, y)) == -sign (tree_cmp (y, x)) and the incorrect form of the assertion doesn't hold e.g. on s390x where for certain inputs x, y, tree_cmp (x, y) == 1 and tree_cmp (y, x) == -2, breaking the build in "make selftest" in stage1. In any case, these checks are redundant, since qsort_chk performs them. Additionally, there is a potential lack of transitivity in worklist::key_t::cmp where hashval_t values are compared by subtraction, which could fail to be transitive if overflows occur. This patch eliminates the redundant checks and reimplements the hashval_t comparisons in terms of < and >, fixing these issues. gcc/analyzer/ChangeLog: * call-string.cc (call_string::cmp_1): Delete, moving body to... (call_string::cmp): ...here. * call-string.h (call_string::cmp_1): Delete decl. * engine.cc (worklist::key_t::cmp_1): Delete, moving body to... (worklist::key_t::cmp): ...here. Implement hash comparisons via comparison rather than subtraction to avoid overflow issues. * exploded-graph.h (worklist::key_t::cmp_1): Delete decl. * region-model.cc (tree_cmp): Eliminate buggy checking for symmetry.
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