[committed] libstdc++: Use alias template for iterator_category [PR110970]
Checks
Commit Message
Tested x86_64-linux. Pushed to trunk. Backport to gcc-13 to follow.
-- >8 --
This renames __iterator_category_t to __iter_category_t, for consistency
with std::iter_value_t, std::iter_difference_t and std::iter_reference_t
in C++20. Then use __iter_category_t in <bits/stl_iterator.h>, which
fixes the problem of the missing 'typename' that Clang 15 incorrectly
still requires.
libstdc++-v3/ChangeLog:
PR libstdc++/110970
* include/bits/stl_iterator.h (__detail::__move_iter_cat): Use
__iter_category_t.
(iterator_traits<common_iterator<I, S>>::_S_iter_cat): Likewise.
(__detail::__basic_const_iterator_iter_cat): Likewise.
* include/bits/stl_iterator_base_types.h (__iterator_category_t):
Rename to __iter_category_t.
---
libstdc++-v3/include/bits/stl_iterator.h | 17 +++++++++--------
.../include/bits/stl_iterator_base_types.h | 6 +++---
2 files changed, 12 insertions(+), 11 deletions(-)
Comments
On Thu, 10 Aug 2023 at 23:34, Jonathan Wakely via Libstdc++ <
libstdc++@gcc.gnu.org> wrote:
> Tested x86_64-linux. Pushed to trunk. Backport to gcc-13 to follow.
>
> -- >8 --
>
> This renames __iterator_category_t to __iter_category_t, for consistency
> with std::iter_value_t, std::iter_difference_t and std::iter_reference_t
> in C++20. Then use __iter_category_t in <bits/stl_iterator.h>, which
> fixes the problem of the missing 'typename' that Clang 15 incorrectly
> still requires.
>
> libstdc++-v3/ChangeLog:
>
> PR libstdc++/110970
> * include/bits/stl_iterator.h (__detail::__move_iter_cat): Use
> __iter_category_t.
> (iterator_traits<common_iterator<I, S>>::_S_iter_cat): Likewise.
> (__detail::__basic_const_iterator_iter_cat): Likewise.
> * include/bits/stl_iterator_base_types.h (__iterator_category_t):
> Rename to __iter_category_t.
> ---
> libstdc++-v3/include/bits/stl_iterator.h | 17 +++++++++--------
> .../include/bits/stl_iterator_base_types.h | 6 +++---
> 2 files changed, 12 insertions(+), 11 deletions(-)
>
> diff --git a/libstdc++-v3/include/bits/stl_iterator.h
> b/libstdc++-v3/include/bits/stl_iterator.h
> index b22d9a4fdb3..d5ba05f3e22 100644
> --- a/libstdc++-v3/include/bits/stl_iterator.h
> +++ b/libstdc++-v3/include/bits/stl_iterator.h
> @@ -103,6 +103,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
> using __clamp_iter_cat
> = __conditional_t<derived_from<_Cat, _Limit>, _Limit, _Otherwise>;
>
> + template<typename _Iter, typename _Limit>
> + using __clamped_iter_cat_t
> + = __clamp_iter_cat<__iter_category_t<_Iter>, _Limit>;
> +
> template<typename _Tp, typename _Up>
> concept __different_from
> = !same_as<remove_cvref_t<_Tp>, remove_cvref_t<_Up>>;
> @@ -168,8 +172,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
> random_access_iterator_tag,
> bidirectional_iterator_tag>;
> using iterator_category
> - = __detail::__clamp_iter_cat<typename
> __traits_type::iterator_category,
> - random_access_iterator_tag>;
> + = __detail::__clamped_iter_cat_t<_Iterator,
> random_access_iterator_tag>;
> using value_type = iter_value_t<_Iterator>;
> using difference_type = iter_difference_t<_Iterator>;
> using reference = iter_reference_t<_Iterator>;
> @@ -1426,12 +1429,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
> { };
>
> template<typename _Iterator>
> - requires requires { typename
> iterator_traits<_Iterator>::iterator_category; }
> + requires requires { typename __iter_category_t<_Iterator>; }
> struct __move_iter_cat<_Iterator>
> {
> using iterator_category
> - = __clamp_iter_cat<typename
> iterator_traits<_Iterator>::iterator_category,
> - random_access_iterator_tag>;
> + = __clamped_iter_cat_t<_Iterator, random_access_iterator_tag>;
>
Oops, I only meant to commit the change to use __iter_category_t, not the
addition of __clamped_iter_cat. I'll revert that part. It was an experiment
that I decided against, and I thought I'd already reverted before
committing.
> };
> #endif
> }
> @@ -2288,8 +2290,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
> static auto
> _S_iter_cat()
> {
> - using _Traits = iterator_traits<_It>;
> - if constexpr (requires { requires derived_from<typename
> _Traits::iterator_category,
> + if constexpr (requires { requires
> derived_from<__iter_category_t<_It>,
>
> forward_iterator_tag>; })
> return forward_iterator_tag{};
> else
> @@ -2615,7 +2616,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>
> template<forward_iterator _It>
> struct __basic_const_iterator_iter_cat<_It>
> - { using iterator_category =
> iterator_traits<_It>::iterator_category; };
> + { using iterator_category = __iter_category_t<_It>; };
> } // namespace detail
>
> template<input_iterator _It>
> diff --git a/libstdc++-v3/include/bits/stl_iterator_base_types.h
> b/libstdc++-v3/include/bits/stl_iterator_base_types.h
> index 5d2c8b325d9..841b5eca3ad 100644
> --- a/libstdc++-v3/include/bits/stl_iterator_base_types.h
> +++ b/libstdc++-v3/include/bits/stl_iterator_base_types.h
> @@ -243,16 +243,16 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
>
> #if __cplusplus >= 201103L
> template<typename _Iter>
> - using __iterator_category_t
> + using __iter_category_t
> = typename iterator_traits<_Iter>::iterator_category;
>
> template<typename _InIter>
> using _RequireInputIter =
> - __enable_if_t<is_convertible<__iterator_category_t<_InIter>,
> + __enable_if_t<is_convertible<__iter_category_t<_InIter>,
> input_iterator_tag>::value>;
>
> template<typename _It,
> - typename _Cat = __iterator_category_t<_It>>
> + typename _Cat = __iter_category_t<_It>>
> struct __is_random_access_iter
> : is_base_of<random_access_iterator_tag, _Cat>
> {
> --
> 2.41.0
>
>
@@ -103,6 +103,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
using __clamp_iter_cat
= __conditional_t<derived_from<_Cat, _Limit>, _Limit, _Otherwise>;
+ template<typename _Iter, typename _Limit>
+ using __clamped_iter_cat_t
+ = __clamp_iter_cat<__iter_category_t<_Iter>, _Limit>;
+
template<typename _Tp, typename _Up>
concept __different_from
= !same_as<remove_cvref_t<_Tp>, remove_cvref_t<_Up>>;
@@ -168,8 +172,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
random_access_iterator_tag,
bidirectional_iterator_tag>;
using iterator_category
- = __detail::__clamp_iter_cat<typename __traits_type::iterator_category,
- random_access_iterator_tag>;
+ = __detail::__clamped_iter_cat_t<_Iterator, random_access_iterator_tag>;
using value_type = iter_value_t<_Iterator>;
using difference_type = iter_difference_t<_Iterator>;
using reference = iter_reference_t<_Iterator>;
@@ -1426,12 +1429,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
{ };
template<typename _Iterator>
- requires requires { typename iterator_traits<_Iterator>::iterator_category; }
+ requires requires { typename __iter_category_t<_Iterator>; }
struct __move_iter_cat<_Iterator>
{
using iterator_category
- = __clamp_iter_cat<typename iterator_traits<_Iterator>::iterator_category,
- random_access_iterator_tag>;
+ = __clamped_iter_cat_t<_Iterator, random_access_iterator_tag>;
};
#endif
}
@@ -2288,8 +2290,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
static auto
_S_iter_cat()
{
- using _Traits = iterator_traits<_It>;
- if constexpr (requires { requires derived_from<typename _Traits::iterator_category,
+ if constexpr (requires { requires derived_from<__iter_category_t<_It>,
forward_iterator_tag>; })
return forward_iterator_tag{};
else
@@ -2615,7 +2616,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
template<forward_iterator _It>
struct __basic_const_iterator_iter_cat<_It>
- { using iterator_category = iterator_traits<_It>::iterator_category; };
+ { using iterator_category = __iter_category_t<_It>; };
} // namespace detail
template<input_iterator _It>
@@ -243,16 +243,16 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
#if __cplusplus >= 201103L
template<typename _Iter>
- using __iterator_category_t
+ using __iter_category_t
= typename iterator_traits<_Iter>::iterator_category;
template<typename _InIter>
using _RequireInputIter =
- __enable_if_t<is_convertible<__iterator_category_t<_InIter>,
+ __enable_if_t<is_convertible<__iter_category_t<_InIter>,
input_iterator_tag>::value>;
template<typename _It,
- typename _Cat = __iterator_category_t<_It>>
+ typename _Cat = __iter_category_t<_It>>
struct __is_random_access_iter
: is_base_of<random_access_iterator_tag, _Cat>
{