On Wed, 28 Feb 2024, Ken Matsui wrote:
> This patch optimizes the compilation performance of
> std::is_nothrow_invocable by dispatching to the new
> __is_nothrow_invocable built-in trait.
>
> libstdc++-v3/ChangeLog:
>
> * include/std/type_traits (is_nothrow_invocable): Use
> __is_nothrow_invocable built-in trait.
> * testsuite/20_util/is_nothrow_invocable/incomplete_args_neg.cc:
> Handle the new error from __is_nothrow_invocable.
> * testsuite/20_util/is_nothrow_invocable/incomplete_neg.cc:
> Likewise.
>
> Signed-off-by: Ken Matsui <kmat...@gcc.gnu.org>
> ---
> libstdc++-v3/include/std/type_traits | 4 ++++
> .../20_util/is_nothrow_invocable/incomplete_args_neg.cc | 1 +
> .../testsuite/20_util/is_nothrow_invocable/incomplete_neg.cc | 1 +
> 3 files changed, 6 insertions(+)
>
> diff --git a/libstdc++-v3/include/std/type_traits
> b/libstdc++-v3/include/std/type_traits
> index 9af233bcc75..093d85a51a8 100644
> --- a/libstdc++-v3/include/std/type_traits
> +++ b/libstdc++-v3/include/std/type_traits
> @@ -3265,8 +3265,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
> /// std::is_nothrow_invocable
> template<typename _Fn, typename... _ArgTypes>
> struct is_nothrow_invocable
> +#if _GLIBCXX_USE_BUILTIN_TRAIT(__is_nothrow_invocable)
> + : public __bool_constant<__is_nothrow_invocable(_Fn, _ArgTypes...)>
> +#else
> : __and_<__is_invocable_impl<__invoke_result<_Fn, _ArgTypes...>, void>,
> __call_is_nothrow_<_Fn, _ArgTypes...>>::type
> +#endif
> {
> static_assert(std::__is_complete_or_unbounded(__type_identity<_Fn>{}),
> "_Fn must be a complete class or an unbounded array");
> diff --git
> a/libstdc++-v3/testsuite/20_util/is_nothrow_invocable/incomplete_args_neg.cc
> b/libstdc++-v3/testsuite/20_util/is_nothrow_invocable/incomplete_args_neg.cc
> index 3c225883eaf..3f8542dd366 100644
> ---
> a/libstdc++-v3/testsuite/20_util/is_nothrow_invocable/incomplete_args_neg.cc
> +++
> b/libstdc++-v3/testsuite/20_util/is_nothrow_invocable/incomplete_args_neg.cc
> @@ -18,6 +18,7 @@
> // <http://www.gnu.org/licenses/>.
>
> // { dg-error "must be a complete class" "" { target *-*-* } 0 }
> +// { dg-prune-output "invalid use of incomplete type" }
Is the error coming somewhere from the new build_invoke function? That'd
be surprising since we pass tf_none to it, which should suppress such
errors. (You can probably break on cxx_incomplete_type_diagnostic to
find out where it's coming from.)
>
> #include <type_traits>
>
> diff --git
> a/libstdc++-v3/testsuite/20_util/is_nothrow_invocable/incomplete_neg.cc
> b/libstdc++-v3/testsuite/20_util/is_nothrow_invocable/incomplete_neg.cc
> index 5a728bfa03b..d3bdf08448b 100644
> --- a/libstdc++-v3/testsuite/20_util/is_nothrow_invocable/incomplete_neg.cc
> +++ b/libstdc++-v3/testsuite/20_util/is_nothrow_invocable/incomplete_neg.cc
> @@ -18,6 +18,7 @@
> // <http://www.gnu.org/licenses/>.
>
> // { dg-error "must be a complete class" "" { target *-*-* } 0 }
> +// { dg-prune-output "invalid use of incomplete type" }
>
> #include <type_traits>
>
> --
> 2.44.0
>
>
