https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97860
--- Comment #8 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:8156cfaa4c45f1249bbdda29d04b4fef84b7eafe commit r11-5180-g8156cfaa4c45f1249bbdda29d04b4fef84b7eafe Author: Jakub Jelinek <ja...@redhat.com> Date: Thu Nov 19 20:02:41 2020 +0100 c, tree: Fix ICE from get_parm_array_spec [PR97860] The C and C++ FEs handle zero sized arrays differently, C uses NULL TYPE_MAX_VALUE on non-NULL TYPE_DOMAIN on complete ARRAY_TYPEs with bitsize_zero_node TYPE_SIZE, while C++ FE likes to set TYPE_MAX_VALUE to the largest value (and min to the lowest). Martin has used array_type_nelts in get_parm_array_spec where the function on the C form of [0] arrays returns error_mark_node and the code crashes soon afterwards. The following patch teaches array_type_nelts about this (e.g. dwarf2out already handles that as [0]). While it will change what is_empty_type returns for certain types (e.g. struct S { int a[0]; };), as those types occupy zero bits in C, it should make an ABI difference. So, the tree.c change makes the c-decl.c code handle the [0] arrays like any other constant extents, and the c-decl.c change just makes sure that if we'd run into error_mark_node e.g. from the VLA expressions, we don't crash on those. 2020-11-19 Jakub Jelinek <ja...@redhat.com> PR c/97860 * tree.c (array_type_nelts): For complete arrays with zero min and NULL max and zero size return -1. * c-decl.c (get_parm_array_spec): Bail out of nelts is error_operand_p. * gcc.dg/pr97860.c: New test.
