+++ This bug was initially created as a clone of Bug #113798 +++ As mentioned in the https://wg21.link/P2662R3 paper, we aren't parsing correctly T...[N] parameters. template <int N, typename ...T> void foo (T... x[N]) { } template <int N, typename T> void bar (T [N]) { } template <int N, typename ...T> void baz (T... [N]) { } template <int N, typename ...T> void qux (T... [N][N]) { } void corge (int a[10], double b[10], int c[5][5], float d[5][5]) { foo <10, int, double> (a, b); bar <10, int> (a); baz <10, int, double> (a, b); qux <5, int, float> (c, d); } is accepted by clang++ but not by GCC nor MSCV. This is going to change in C++26 with pack indexing, but in C++11 .. C++23 it should be valid.
Created attachment 58147 [details] gcc15-pr115012.patch Untested fix.
Created attachment 58148 [details] gcc15-pr115012.patch Updated patch which also handles the T...(args) case.
The master branch has been updated by Jakub Jelinek <jakub@gcc.gnu.org>: https://gcc.gnu.org/g:48c3e5a4f935d6b8cd9ef7c51995e3b29ceb8be7 commit r15-1000-g48c3e5a4f935d6b8cd9ef7c51995e3b29ceb8be7 Author: Jakub Jelinek <jakub@redhat.com> Date: Mon Jun 3 23:07:08 2024 +0200 c++: Fix parsing of abstract-declarator starting with ... followed by opening paren [PR115012] The C++26 P2662R3 Pack indexing paper mentions that both GCC and MSVC don't handle T...[10] parameter declaration when T is a pack. And apparently neither T...(args). While the former will change meaning in C++26, T...(args) is still valid even in C++26. The following patch handles just the T...(args) case in cp_parser_direct_declarator. 2024-06-03 Jakub Jelinek <jakub@redhat.com> PR c++/115012 * parser.cc (cp_parser_direct_declarator): Handle abstract declarator starting with ... followed by opening paren. * g++.dg/cpp0x/variadic185.C: New test.