https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93789
--- Comment #3 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Marek Polacek <mpola...@gcc.gnu.org>: https://gcc.gnu.org/g:1231f71f96a4e461f94394b4fb8cfa25587fbd96 commit r10-6881-g1231f71f96a4e461f94394b4fb8cfa25587fbd96 Author: Marek Polacek <pola...@redhat.com> Date: Wed Feb 26 15:02:25 2020 -0500 c++: Fix ICE with invalid array bounds [PR93789] r7-2111 introduced maybe_constant_value in cp_fully_fold. maybe_constant_value uses cxx_eval_outermost_constant_expr, which can clear TREE_CONSTANT: 6510 else if (non_constant_p && TREE_CONSTANT (r)) [...] 6529 TREE_CONSTANT (r) = false; In this test the array size is '(long int) "h"'. This used to be TREE_CONSTANT but given the change above, the flag will be cleared when we cp_fully_fold the array size in compute_array_index_type_loc. That means we don't emit an error in the 10391 else if (TREE_CONSTANT (size) block in the same function, and we go on. Then we compute ITYPE using cp_build_binary_op and use maybe_constant_value on it and suddenly we have something that's TREE_CONSTANT again. And then we crash in reshape_init_array_1 in tree_to_uhwi, because what we have doesn't fit in an unsigned HWI. icc accepts this code, but since we used to reject it, I see no desire to make this work, so don't use the folded result when we've lost the TREE_CONSTANT flag while evaluating the size. 2020-02-26 Marek Polacek <pola...@redhat.com> PR c++/93789 - ICE with invalid array bounds. * decl.c (compute_array_index_type_loc): Don't use the folded size when folding cleared TREE_CONSTANT. * g++.dg/ext/vla22.C: New test.
