https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123729
--- Comment #3 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Richard Biener <[email protected]>: https://gcc.gnu.org/g:06765f2e0fc4991e08adda7f72902edfb7e70fbb commit r16-6915-g06765f2e0fc4991e08adda7f72902edfb7e70fbb Author: Richard Biener <[email protected]> Date: Tue Jan 20 10:24:20 2026 +0100 tree-optimization/123729 - fix reduction epilog flowing into abnormal edge When we vectorize a reduction and the reduction value flows across an abnormal edge we have to make sure to mark the final SSA properly. The following serves as a recipie how to avoid blindly copying SSA_NAME_OCCURS_IN_ABNORMAL_PHI but instead set it when needed during use replacement. PR tree-optimization/123729 * tree-vect-loop.cc (vect_create_epilog_for_reduction): Set SSA_NAME_OCCURS_IN_ABNORMAL_PHI if the reduction flows across an abnomal edge. * g++.dg/torture/pr123729.C: New testcase.
