Ooh... Thank you for pointing that out!
> The helper doesn't need to be defined for the case where we don't use it.
I thought that macroing them out leads to compiler errors since users
are possibly using those helpers. But do we not have to care about
that?
---
libstdc++-v3/ChangeLog:
* include/std/type_traits (remove_pointer): Use __remove_pointer built-in trait.
---
diff --git a/libstdc++-v3/include/std/type_traits
b/libstdc++-v3/include/std/type_traits
index 2bd607a8b8f..cba98091aad 100644
--- a/libstdc++-v3/include/std/type_traits
+++ b/libstdc++-v3/include/std/type_traits
@@ -2025,17 +2025,23 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
template<typename _Tp, typename>
struct __remove_pointer_helper
- { typedef _Tp type; };
+ { using type = _Tp; };
template<typename _Tp, typename _Up>
struct __remove_pointer_helper<_Tp, _Up*>
- { typedef _Up type; };
+ { using type = _Up; };
/// remove_pointer
+#if __has_builtin(__remove_pointer)
+ template<typename _Tp>
+ struct remove_pointer
+ { using type = __remove_pointer(_Tp); };
+#else
template<typename _Tp>
struct remove_pointer
: public __remove_pointer_helper<_Tp, __remove_cv_t<_Tp>>
{ };
+#endif
template<typename _Tp, typename = void>
struct __add_pointer_helper
On Mon, Mar 20, 2023 at 12:57 AM Jonathan Wakely <jwakely....@gmail.com> wrote:
>
>
>
> On Mon, 20 Mar 2023, 07:32 Ken Matsui via Libstdc++, <libstd...@gcc.gnu.org>
> wrote:
>>
>> CCing libstd...@gcc.gnu.org.
>>
>> On Sun, Mar 19, 2023 at 7:53 PM Ken Matsui <kmat...@cs.washington.edu> wrote:
>> >
>> > libstdc++-v3/ChangeLog:
>> >
>> > * include/std/type_traits (is_reference): Use __remove_pointer built-in
>> > trait.
>
>
> The changelog entry says is_reference but the patch is for remove_pointer.
>
>
>> >
>> > ---
>> > diff --git a/libstdc++-v3/include/std/type_traits
>> > b/libstdc++-v3/include/std/type_traits
>> > index 2bd607a8b8f..cba98091aad 100644
>> > --- a/libstdc++-v3/include/std/type_traits
>> > +++ b/libstdc++-v3/include/std/type_traits
>> > @@ -2025,17 +2025,23 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>> >
>> > template<typename _Tp, typename>
>> > struct __remove_pointer_helper
>> > - { typedef _Tp type; };
>> > + { using type = _Tp; };
>> >
>> > template<typename _Tp, typename _Up>
>> > struct __remove_pointer_helper<_Tp, _Up*>
>> > - { typedef _Up type; };
>> > + { using type = _Up; };
>
>
> The helper doesn't need to be defined for the case where we don't use it.
>
>
>> >
>> > /// remove_pointer
>> > +#if __has_builtin(__remove_pointer)
>> > + template<typename _Tp>
>> > + struct remove_pointer
>> > + { using type = __remove_pointer(_Tp); };
>> > +#else
>> > template<typename _Tp>
>> > struct remove_pointer
>> > : public __remove_pointer_helper<_Tp, __remove_cv_t<_Tp>>
>> > { };
>> > +#endif
>> >
>> > template<typename _Tp, typename = void>
>> > struct __add_pointer_helper
