https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100887
--- Comment #13 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-11 branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:ce1dd5e70514fde8e34c86ab45a3c55e84d3c5b7 commit r11-8590-gce1dd5e70514fde8e34c86ab45a3c55e84d3c5b7 Author: Jakub Jelinek <ja...@redhat.com> Date: Mon Jun 7 09:28:31 2021 +0200 fold-const: Fix up fold_read_from_vector [PR100887] The callers of fold_read_from_vector expect that the index they pass is an index of an element in the vector and the function does that most of the time. But we allow CONSTRUCTORs with VECTOR_TYPE to have VECTOR_TYPE elements and in that case every CONSTRUCTOR element represents not just one index (with the exception of V1 vectors), but multiple. So returning zero vector if i >= CONSTRUCTOR_NELTS or returning some CONSTRUCTOR_ELT's value might not be what the callers expect. Fixed by punting if the first element has vector type. Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? In theory we could instead recurse (and assert that for CONSTRUCTORs of vector elements we have always all elements specified like tree-cfg.c verifies?) after adjusting the index appropriately. 2021-06-07 Jakub Jelinek <ja...@redhat.com> PR target/100887 * fold-const.c (fold_read_from_vector): Return NULL if trying to read from a CONSTRUCTOR with vector type elements. (cherry picked from commit e1521b170b44be5cd5d36a98b6b760457b68f566)
