[libc++][mdspan] P3383R3: mdspan.at()#175213
Merged
Merged
Conversation
llvmbot
added
the
libc++
Member
|
@llvm/pr-subscribers-libcxx Author: eiytoq (eiytoq) ChangesImplements https://wg21.link/P3383R3 Closes #148149 Patch is 23.74 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/175213.diff 11 Files Affected:
diff --git a/libcxx/docs/FeatureTestMacroTable.rst b/libcxx/docs/FeatureTestMacroTable.rst
index 32911d0f64449..abe478b6a8d2b 100644
--- a/libcxx/docs/FeatureTestMacroTable.rst
+++ b/libcxx/docs/FeatureTestMacroTable.rst
@@ -484,7 +484,7 @@ Status
---------------------------------------------------------- -----------------
``__cpp_lib_linalg`` *unimplemented*
---------------------------------------------------------- -----------------
- ``__cpp_lib_mdspan`` ``202406L``
+ ``__cpp_lib_mdspan`` ``202506L``
---------------------------------------------------------- -----------------
``__cpp_lib_not_fn`` ``202306L``
---------------------------------------------------------- -----------------
diff --git a/libcxx/docs/Status/Cxx2cPapers.csv b/libcxx/docs/Status/Cxx2cPapers.csv
index 29642fc53cac6..93843450b5cba 100644
--- a/libcxx/docs/Status/Cxx2cPapers.csv
+++ b/libcxx/docs/Status/Cxx2cPapers.csv
@@ -134,7 +134,7 @@
"`P3480R6 <https://wg21.link/P3480R6>`__","``std::simd`` is a range","2025-06 (Sofia)","","","`#148144 <https://github.com/llvm/llvm-project/issues/148144>`__",""
"`P2664R11 <https://wg21.link/P2664R11>`__","Extend ``std::simd`` with permutation API","2025-06 (Sofia)","","","`#148145 <https://github.com/llvm/llvm-project/issues/148145>`__",""
"`P3691R1 <https://wg21.link/P3691R1>`__","Reconsider naming of the namespace for ``std::simd``","2025-06 (Sofia)","","","`#148148 <https://github.com/llvm/llvm-project/issues/148148>`__",""
-"`P3383R3 <https://wg21.link/P3383R3>`__","``mdspan.at()``","2025-06 (Sofia)","","","`#148149 <https://github.com/llvm/llvm-project/issues/148149>`__",""
+"`P3383R3 <https://wg21.link/P3383R3>`__","``mdspan.at()``","2025-06 (Sofia)","|Complete|","22","`#148149 <https://github.com/llvm/llvm-project/issues/148149>`__",""
"`P2927R3 <https://wg21.link/P2927R3>`__","Inspecting ``exception_ptr``","2025-06 (Sofia)","","","`#148150 <https://github.com/llvm/llvm-project/issues/148150>`__",""
"`P3748R0 <https://wg21.link/P3748R0>`__","Inspecting ``exception_ptr`` should be constexpr","2025-06 (Sofia)","","","`#148151 <https://github.com/llvm/llvm-project/issues/148151>`__",""
"`P2830R10 <https://wg21.link/P2830R10>`__","Standardized Constexpr Type Ordering","2025-06 (Sofia)","","","`#148152 <https://github.com/llvm/llvm-project/issues/148152>`__",""
diff --git a/libcxx/include/__mdspan/mdspan.h b/libcxx/include/__mdspan/mdspan.h
index 9d3d35cd558a1..d32aa355c7305 100644
--- a/libcxx/include/__mdspan/mdspan.h
+++ b/libcxx/include/__mdspan/mdspan.h
@@ -40,6 +40,9 @@
#include <__utility/integer_sequence.h>
#include <array>
#include <span>
+#if _LIBCPP_STD_VER >= 26
+# include <stdexcept>
+#endif
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -214,6 +217,37 @@ class mdspan {
}(make_index_sequence<rank()>()));
}
+# if _LIBCPP_STD_VER >= 26
+ template <class... _OtherIndexTypes>
+ requires((is_convertible_v<_OtherIndexTypes, index_type> && ...) &&
+ (is_nothrow_constructible_v<index_type, _OtherIndexTypes> && ...) &&
+ (sizeof...(_OtherIndexTypes) == rank()))
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr reference at(_OtherIndexTypes... __indices) const {
+ if (!__mdspan_detail::__is_multidimensional_index_in(__map_.extents(), __indices...)) {
+ __throw_out_of_range();
+ }
+ return operator[](static_cast<index_type>(std::move(__indices))...);
+ }
+
+ template <class _OtherIndexType>
+ requires(is_convertible_v<const _OtherIndexType&, index_type> &&
+ is_nothrow_constructible_v<index_type, const _OtherIndexType&>)
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr reference at(const array<_OtherIndexType, rank()>& __indices) const {
+ return [&]<size_t... _Idxs>(index_sequence<_Idxs...>) -> reference {
+ return at(static_cast<index_type>(__indices[_Idxs])...);
+ }(make_index_sequence<rank()>());
+ }
+
+ template <class _OtherIndexType>
+ requires(is_convertible_v<const _OtherIndexType&, index_type> &&
+ is_nothrow_constructible_v<index_type, const _OtherIndexType&>)
+ [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr reference at(span<_OtherIndexType, rank()> __indices) const {
+ return [&]<size_t... _Idxs>(index_sequence<_Idxs...>) -> reference {
+ return at(static_cast<index_type>(__indices[_Idxs])...);
+ }(make_index_sequence<rank()>());
+ }
+# endif
+
[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr size_type size() const noexcept {
// Could leave this as only checked in debug mode: semantically size() is never
// guaranteed to be related to any accessible range
@@ -270,6 +304,10 @@ class mdspan {
template <class, class, class, class>
friend class mdspan;
+
+# if _LIBCPP_VERSION >= 26
+ [[noreturn]] _LIBCPP_HIDE_FROM_ABI void __throw_out_of_range() const { std::__throw_out_of_range("mdspan"); }
+# endif
};
# if _LIBCPP_STD_VER >= 26
diff --git a/libcxx/include/mdspan b/libcxx/include/mdspan
index 32468a128dc9a..f85353cc9d758 100644
--- a/libcxx/include/mdspan
+++ b/libcxx/include/mdspan
@@ -364,6 +364,13 @@ namespace std {
template<class OtherIndexType>
constexpr reference operator[](const array<OtherIndexType, rank()>& indices) const;
+ template<class... OtherIndexTypes>
+ constexpr reference at(OtherIndexTypes... indices) const;
+ template<class OtherIndexType>
+ constexpr reference at(span<OtherIndexType, rank()> indices) const;
+ template<class OtherIndexType>
+ constexpr reference at(const array<OtherIndexType, rank()>& indices) const;
+
constexpr size_type size() const noexcept;
[[nodiscard]] constexpr bool empty() const noexcept;
diff --git a/libcxx/include/version b/libcxx/include/version
index 1d2422e64ba0f..1049ff7188463 100644
--- a/libcxx/include/version
+++ b/libcxx/include/version
@@ -174,7 +174,7 @@ __cpp_lib_make_unique 201304L <memory>
__cpp_lib_map_try_emplace 201411L <map>
__cpp_lib_math_constants 201907L <numbers>
__cpp_lib_math_special_functions 201603L <cmath>
-__cpp_lib_mdspan 202406L <mdspan>
+__cpp_lib_mdspan 202506L <mdspan>
202207L // C++23
__cpp_lib_memory_resource 201603L <memory_resource>
__cpp_lib_move_iterator_concept 202207L <iterator>
@@ -593,7 +593,7 @@ __cpp_lib_void_t 201411L <type_traits>
# endif
// # define __cpp_lib_linalg 202311L
# undef __cpp_lib_mdspan
-# define __cpp_lib_mdspan 202406L
+# define __cpp_lib_mdspan 202506L
# undef __cpp_lib_not_fn
# define __cpp_lib_not_fn 202306L
# undef __cpp_lib_optional
diff --git a/libcxx/test/libcxx/containers/views/mdspan/nodiscard.verify.cpp b/libcxx/test/libcxx/containers/views/mdspan/nodiscard.verify.cpp
index d248656ec0ae5..b132c4a6da09b 100644
--- a/libcxx/test/libcxx/containers/views/mdspan/nodiscard.verify.cpp
+++ b/libcxx/test/libcxx/containers/views/mdspan/nodiscard.verify.cpp
@@ -28,6 +28,10 @@ void test() {
std::span sp{arr};
mdsp[sp]; // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
+ mdsp.at(0, 1); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
+ mdsp.at(arr); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
+ mdsp.at(sp); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
+
mdsp.rank(); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
mdsp.rank_dynamic(); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
mdsp.static_extent(0); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
diff --git a/libcxx/test/std/containers/views/mdspan/CustomTestLayouts.h b/libcxx/test/std/containers/views/mdspan/CustomTestLayouts.h
index 588a5e9774a55..4b33f11dc0086 100644
--- a/libcxx/test/std/containers/views/mdspan/CustomTestLayouts.h
+++ b/libcxx/test/std/containers/views/mdspan/CustomTestLayouts.h
@@ -335,4 +335,80 @@ class always_convertible_layout::mapping {
index_type offset_{};
index_type scaling_{};
};
+
+struct SpyIndex {
+ int val;
+ constexpr SpyIndex(int v) : val(v) {}
+ constexpr operator int() const noexcept { return val; }
+};
+
+class strict_cast_layout {
+public:
+ template <class Extents>
+ class mapping;
+};
+
+template <class Extents>
+class strict_cast_layout::mapping {
+public:
+ using extents_type = Extents;
+ using index_type = typename extents_type::index_type;
+ using size_type = typename extents_type::size_type;
+ using rank_type = typename extents_type::rank_type;
+ using layout_type = strict_cast_layout;
+
+ constexpr mapping() noexcept = default;
+ constexpr mapping(const mapping&) noexcept = default;
+ constexpr mapping(const extents_type& ext) noexcept : extents_(ext) {}
+
+ template <class OtherExtents>
+ constexpr mapping(const mapping<OtherExtents>& other) noexcept : extents_(other.extents()) {}
+
+ constexpr mapping& operator=(const mapping&) noexcept = default;
+
+ constexpr const extents_type& extents() const noexcept { return extents_; }
+
+ constexpr index_type required_span_size() const noexcept {
+ index_type size = 1;
+ for (rank_type r = 0; r < extents_type::rank(); r++)
+ size *= extents_.extent(r);
+ return size;
+ }
+
+ template <std::integral... Indices>
+ requires(sizeof...(Indices) == extents_type::rank())
+ constexpr index_type operator()(Indices... idx) const noexcept {
+ return [&]<size_t... _Is>(std::index_sequence<_Is...>) {
+ index_type res = 0;
+ std::array<index_type, sizeof...(Indices)> idx_arr{static_cast<index_type>(idx)...};
+ ((res = res * extents_.extent(_Is) + idx_arr[_Is]), ...);
+ return res;
+ }(std::make_index_sequence<sizeof...(Indices)>{});
+ }
+
+ constexpr index_type operator()(SpyIndex) const noexcept = delete;
+
+ static constexpr bool is_always_unique() noexcept { return true; }
+ static constexpr bool is_always_exhaustive() noexcept { return true; }
+ static constexpr bool is_always_strided() noexcept { return true; }
+
+ static constexpr bool is_unique() noexcept { return true; }
+ static constexpr bool is_exhaustive() noexcept { return true; }
+ static constexpr bool is_strided() noexcept { return true; }
+
+ constexpr index_type stride(rank_type r) const noexcept {
+ index_type s = 1;
+ for (rank_type i = r + 1; i < extents_type::rank(); i++)
+ s *= extents_.extent(i);
+ return s;
+ }
+
+ friend constexpr bool operator==(const mapping& lhs, const mapping& rhs) noexcept {
+ return lhs.extents_ == rhs.extents_;
+ }
+
+private:
+ extents_type extents_{};
+};
+
#endif // TEST_STD_CONTAINERS_VIEWS_MDSPAN_CUSTOM_TEST_LAYOUTS_H
diff --git a/libcxx/test/std/containers/views/mdspan/mdspan/at.pass.cpp b/libcxx/test/std/containers/views/mdspan/mdspan/at.pass.cpp
new file mode 100644
index 0000000000000..8fdb721e5ebe4
--- /dev/null
+++ b/libcxx/test/std/containers/views/mdspan/mdspan/at.pass.cpp
@@ -0,0 +1,262 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20, c++23
+
+// <mdspan>
+
+// template<class... OtherIndexTypes>
+// constexpr reference at(OtherIndexTypes... indices) const;
+//
+// template<class OtherIndexType>
+// constexpr reference at(span<OtherIndexType, rank()> indices) const;
+//
+// template<class OtherIndexType>
+// constexpr reference at(const array<OtherIndexType, rank()>& indices) const;
+//
+// Constraints:
+// * sizeof...(OtherIndexTypes) == extents_type::rank() is true,
+// * (is_convertible_v<OtherIndexTypes, index_type> && ...) is true,
+// * (is_nothrow_constructible_v<index_type, OtherIndexTypes> && ...) is true.
+//
+// Throws:
+// * std::out_of_range if extents_type::index-cast(indices) is not a multidimensional index in extents_.
+
+#include <array>
+#include <cassert>
+#include <mdspan>
+#include <span> // dynamic_extent
+#ifndef TEST_HAS_NO_EXCEPTIONS
+# include <vector>
+#endif
+
+#include "test_macros.h"
+
+#include "../ConvertibleToIntegral.h"
+#include "../CustomTestLayouts.h"
+
+template <class MDS, class... Indices>
+concept at_constraints = requires(MDS m, Indices... idxs) {
+ { m.at(idxs...) } -> std::same_as<typename MDS::reference>;
+};
+
+template <class MDS, class... Indices>
+ requires(at_constraints<MDS, Indices...>)
+constexpr bool check_at_constraints(MDS m, Indices... idxs) {
+ TEST_IGNORE_NODISCARD m.at(idxs...);
+ return true;
+}
+
+template <class MDS, class... Indices>
+constexpr bool check_at_constraints(MDS, Indices...) {
+ return false;
+}
+
+template <class MDS, class... Args>
+constexpr void iterate(MDS mds, Args... args) {
+ constexpr int r = static_cast<int>(MDS::extents_type::rank()) - 1 - static_cast<int>(sizeof...(Args));
+
+ if constexpr (r == -1) {
+ [[maybe_unused]] int* ptr_accessor = &(mds.accessor().access(mds.data_handle(), mds.mapping()(args...)));
+ std::array<typename MDS::index_type, MDS::rank()> args_arr{static_cast<typename MDS::index_type>(args)...};
+
+ // mdspan.at(indices...)
+ [[maybe_unused]] typename MDS::element_type* ptr_at = &mds.at(args...);
+ assert(ptr_at == ptr_accessor);
+
+ // mdspan.at(array)
+ [[maybe_unused]] typename MDS::element_type* ptr_arr = &mds.at(args_arr);
+ assert(&mds.at(args_arr) == ptr_accessor);
+
+ // mdspan.at(span)
+ [[maybe_unused]] typename MDS::element_type* ptr_span = &mds.at(std::span(args_arr));
+ assert(ptr_span == ptr_accessor);
+
+ } else {
+ for (typename MDS::index_type i = 0; i < mds.extents().extent(r); i++) {
+ iterate(mds, i, args...);
+ }
+ }
+}
+
+template <class Mapping>
+constexpr void test_iteration(Mapping m) {
+ std::array<int, 1024> data;
+ using MDS = std::mdspan<int, typename Mapping::extents_type, typename Mapping::layout_type>;
+ MDS mds(data.data(), m);
+ iterate(mds);
+}
+
+template <class Layout>
+constexpr void test_layout() {
+ constexpr size_t D = std::dynamic_extent;
+ test_iteration(construct_mapping(Layout(), std::extents<int>()));
+ test_iteration(construct_mapping(Layout(), std::extents<unsigned, D>(1)));
+ test_iteration(construct_mapping(Layout(), std::extents<unsigned, D>(7)));
+ test_iteration(construct_mapping(Layout(), std::extents<unsigned, 7>()));
+ test_iteration(construct_mapping(Layout(), std::extents<unsigned, 7, 8>()));
+ test_iteration(construct_mapping(Layout(), std::extents<signed char, D, D, D, D>(1, 1, 1, 1)));
+
+ int data[1];
+ // Check at constraint for number of arguments
+ static_assert(check_at_constraints(std::mdspan(data, construct_mapping(Layout(), std::extents<int, D>(1))), 0));
+ static_assert(!check_at_constraints(std::mdspan(data, construct_mapping(Layout(), std::extents<int, D>(1))), 0, 0));
+
+ // Check at constraint for convertibility of arguments to index_type
+ static_assert(
+ check_at_constraints(std::mdspan(data, construct_mapping(Layout(), std::extents<int, D>(1))), IntType(0)));
+ static_assert(
+ !check_at_constraints(std::mdspan(data, construct_mapping(Layout(), std::extents<unsigned, D>(1))), IntType(0)));
+
+ // Check at constraint for no-throw-constructibility of index_type from arguments
+ static_assert(!check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<unsigned char, D>(1))), IntType(0)));
+
+ // Check that mixed integrals work: note the second one tests that mdspan casts: layout_wrapping_integral does not accept IntType
+ static_assert(check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<unsigned char, D, D>(1, 1))), int(0), size_t(0)));
+ static_assert(check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D, D>(1, 1))), 0uz, IntType(0)));
+
+ constexpr bool t = true;
+ constexpr bool o = false;
+ static_assert(!check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D, D>(1, 1))), 0uz, IntConfig<o, o, t, t>(0)));
+ static_assert(check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D, D>(1, 1))), 0uz, IntConfig<o, t, t, t>(0)));
+ static_assert(check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D, D>(1, 1))), 0uz, IntConfig<o, t, o, t>(0)));
+ static_assert(!check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D, D>(1, 1))), 0uz, IntConfig<t, o, o, t>(0)));
+ static_assert(check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D, D>(1, 1))), 0uz, IntConfig<t, o, t, o>(0)));
+ static_assert(check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D, D>(1, 1))), 0uz, IntConfig<t, t, t, t>(0)));
+
+ // layout_wrapped wouldn't quite work here the way we wrote the check
+ // IntConfig has configurable conversion properties: convert from const&, convert from non-const, no-throw-ctor from const&, no-throw-ctor from non-const
+ if constexpr (std::is_same_v<Layout, std::layout_left>) {
+ static_assert(!check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D>(1))), std::array{IntConfig<o, o, t, t>(0)}));
+ static_assert(!check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D>(1))), std::array{IntConfig<o, t, t, t>(0)}));
+ static_assert(!check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D>(1))), std::array{IntConfig<t, o, o, t>(0)}));
+ static_assert(!check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D>(1))), std::array{IntConfig<t, t, o, t>(0)}));
+ static_assert(check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D>(1))), std::array{IntConfig<t, o, t, o>(0)}));
+ static_assert(check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D>(1))), std::array{IntConfig<t, t, t, t>(0)}));
+
+ {
+ [[maybe_unused]] std::array idx{IntConfig<o, o, t, t>(0)};
+ assert(!check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D>(1))), std::span(idx)));
+ }
+ {
+ [[maybe_unused]] std::array idx{IntConfig<o, t, t, t>(0)};
+ assert(!check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D>(1))), std::span(idx)));
+ }
+ {
+ [[maybe_unused]] std::array idx{IntConfig<t, o, o, t>(0)};
+ assert(!check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D>(1))), std::span(idx)));
+ }
+ {
+ [[maybe_unused]] std::array idx{IntConfig<t, t, o, t>(0)};
+ assert(!check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D>(1))), std::span(idx)));
+ }
+ {
+ [[maybe_unused]] std::array idx{IntConfig<t, o, t, o>(0)};
+ assert(check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D>(1))), std::span(idx)));
+ }
+ {
+ [[maybe_unused]] std::array idx{IntConfig<t, t, t, t>(0)};
+ assert(check_at_constraints(
+ std::mdspan(data, construct_mapping(Layout(), std::extents<int, D>(1))), std::span(idx)));
+ }
+ }
+}
+
+constexpr bool test...
[truncated]
|
eiytoq
force-pushed
the
libcxx-p3383-mdspan-at
branch
2 times, most recently
from
c52f44c to
170f2fe
Compare
H-G-Hristov
reviewed
Jan 10, 2026
H-G-Hristov
left a comment
H-G-Hristov
left a comment
Contributor
There was a problem hiding this comment.
Thank you for working on this. I didn't do a real review, just a few drive-by comments.
eiytoq
force-pushed
the
libcxx-p3383-mdspan-at
branch
from
170f2fe to
69f4f67
Compare
Contributor
Author
|
@H-G-Hristov Thank you for your detailed review. I have addressed all the comments. |
Zingam
reviewed
Jan 10, 2026
eiytoq
force-pushed
the
libcxx-p3383-mdspan-at
branch
from
69f4f67 to
cc0c26c
Compare
H-G-Hristov
reviewed
Jan 11, 2026
philnik777
reviewed
Jan 12, 2026
eiytoq
force-pushed
the
libcxx-p3383-mdspan-at
branch
2 times, most recently
from
31553a4 to
2661c40
Compare
eiytoq
force-pushed
the
libcxx-p3383-mdspan-at
branch
from
473720c to
f7c38d4
Compare
eiytoq
force-pushed
the
libcxx-p3383-mdspan-at
branch
from
f7c38d4 to
e4730e5
Compare
eiytoq
force-pushed
the
libcxx-p3383-mdspan-at
branch
from
e4730e5 to
6b71ec0
Compare
Contributor
Author
|
Ping~ |
eiytoq
force-pushed
the
libcxx-p3383-mdspan-at
branch
from
6b71ec0 to
31fc347
Compare
Contributor
Author
|
Use |
eiytoq
changed the title
mdspan.at()
Contributor
Author
|
Ping. |
frederick-vs-ja
requested changes
May 19, 2026
Comment on lines
+208
to
+209
| constexpr bool t = true; | ||
| constexpr bool o = false; |
Contributor
There was a problem hiding this comment.
No change requested for this.
Current t and o are quite unreadable. Maybe it would be better to refactor IntConfig with scoped enums (e.g. the enumerators could be (const_)conv::{disabled,may_throw,no_throw}) in another PR.
Contributor
Author
There was a problem hiding this comment.
Most of the test code was migrated from index_operator.pass.cpp, and I plan to refactor these tests in the future.
eiytoq
force-pushed
the
libcxx-p3383-mdspan-at
branch
from
f3dd8fc to
23a4220
Compare
Co-authored-by: A. Jiang <de34@live.cn>
Co-authored-by: A. Jiang <de34@live.cn>
frederick-vs-ja
approved these changes
May 22, 2026
frederick-vs-ja
left a comment
frederick-vs-ja
left a comment
Contributor
There was a problem hiding this comment.
LGTM. CI failures are certainly unrelated. Let's merge this.
Contributor
|
Some buildbots (e.g., Arm64 ASan: https://lab.llvm.org/staging/#/builders/42/builds/4697/steps/10/logs/stdio; Arm64 MSan: https://lab.llvm.org/staging/#/builders/7/builds/1687) are failing after this commit landed. Could you please take a look? |
Contributor
Author
|
@thurstond Thanks for the heads-up. I don’t have access to a native AArch64 machine, so I can’t reproduce this locally right now. I took another look and don’t see an obvious issue yet. I can send a patch to XFAIL this while we figure out the problem. |
Contributor
|
@eiytoq @thurstond I'm trying to fix this. It seems that |
Contributor
|
Thanks @eiytoq and @frederick-vs-ja for taking a look! Bots are green now after @frederick-vs-ja's fix #199330. |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
7 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Implements https://wg21.link/P3383R3
Closes #148149