https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96650
--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by David Malcolm <dmalc...@gcc.gnu.org>: https://gcc.gnu.org/g:50ddbd0282e06614b29f0d3f3be5fbe70085a8bd commit r11-3212-g50ddbd0282e06614b29f0d3f3be5fbe70085a8bd Author: David Malcolm <dmalc...@redhat.com> Date: Tue Sep 15 05:51:04 2020 -0400 analyzer: fix ICE when merging constraints w/o transitivity [PR96650] PR analyzer/96650 reports an assertion failure when merging the intersection of two sets of constraints, due to the resulting constraints being infeasible. It turns out that the two input sets were each infeasible if transitivity were considered, but -fanalyzer-transitivity was off. However for this case, the merging code was "discovering" the transitive infeasibility of the intersection of the constraints even when -fanalyzer-transitivity is off, triggering an assertion failure. I attempted various fixes for this, but each of them would have introduced O(N^2) logic into the constraint-handling code into the -fno-analyzer-transitivity case (with N == the number of constraints). This patch fixes the ICE by tweaking the assertion, so that we silently drop such constraints if -fanalyzer-transitivity is off. gcc/analyzer/ChangeLog: PR analyzer/96650 * constraint-manager.cc (merger_fact_visitor::on_fact): Replace assertion that add_constraint succeeded with an assertion that if it fails, -fanalyzer-transitivity is off. gcc/testsuite/ChangeLog: PR analyzer/96650 * gcc.dg/analyzer/pr96650-1-notrans.c: New test. * gcc.dg/analyzer/pr96650-1-trans.c: New test. * gcc.dg/analyzer/pr96650-2-notrans.c: New test. * gcc.dg/analyzer/pr96650-2-trans.c: New test.