https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124487
--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
So as testcase e.g.
template <int I, typename... T>
struct A {
using B = T...[I];
A () requires (requires { B {}; }) {}
};
template <int I, auto... J>
struct C {
using B = decltype (J...[I]);
C () requires (requires { B {}; }) {}
};
template <int I, auto... J>
decltype (J...[I]) foo () { return 0; }
template <int I, typename... T>
T...[I] bar () { return 0; }
template <int I, typename... T>
using D = T...[I];
template <int I, typename... T>
void baz (D <I, int, T...>) {}
void
qux ()
{
A <3, int, long, short, int> a;
C <2, 0, 0LL, 0U, 0L> c;
foo <0, 1> ();
foo <2, 1U, 2L, 3LL, 4.0> ();
bar <0, int> ();
bar <3, unsigned, long, long long, double> ();
baz <0, int> ();
}
?
