https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91953
Marek Polacek <mpolacek at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |mpolacek at gcc dot gnu.org
--- Comment #3 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #2)
> This boils down to
> struct S {};
>
> void
> foo (S s)
> {
> constexpr S x = s;
> }
> which GCC 7 as well as clang accepted, but GCC 8+ rejects.
I think it should be accepted, since S is empty, there's no actual
lvalue-to-rvalue conversion involved.
It works with
using S = decltype(nullptr);
and this works too since GCC 7:
struct A { } a;
constexpr int f (A a) { return 42; }
constexpr int i = f(a);
