https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123657
--- Comment #8 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Victor Do Nascimento <[email protected]>: https://gcc.gnu.org/g:da35ef96f76694d74b0937966db7def510005c76 commit r16-7038-gda35ef96f76694d74b0937966db7def510005c76 Author: Victor Do Nascimento <[email protected]> Date: Mon Jan 19 16:28:26 2026 +0000 vect: Fix outer loop vectorization for nested uncounted loops [PR123657] Given the inability of `expr_invariant_in_loop_p (loop, expr)' to handle the `scev_not_known' node as the expression, an unknown loop bound in the inner loop in a nested set of loops led to `vect_analyze_loop_form' to erroneously consider the outer loop as suitable for vectorization. This introduces the necessary unknown loop iteration count check to ensure correct handling of counted loops with an embedded uncounted loop. gcc/ChangeLog: PR tree-optimization/123657 * tree-vect-loop.cc (vect_analyze_loop_form): Add chrec_dont_know check. gcc/testsuite/ChangeLog: * gcc.dg/vect/vect-uncounted-run_4.c (main): New.
