<mdspan>: Final cleanups (#3852)

Co-authored-by: Stephan T. Lavavej <stl@nuwen.net>
microsoft · Jul 8, 2023 · 2c495f5 · 2c495f5
1 parent 7943441
commit 2c495f5
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Showing 9 changed files with 258 additions and 216 deletions.
diff --git a/stl/inc/mdspan b/stl/inc/mdspan
diff --git a/tests/std/include/test_mdspan_support.hpp b/tests/std/include/test_mdspan_support.hpp
@@ -229,9 +229,9 @@ constexpr void check_members_with_various_extents(Fn&& fn) {
     details::check_members_with_various_extents_impl(std::forward<Fn>(fn), std::make_index_sequence<2>{});
     details::check_members_with_various_extents_impl(std::forward<Fn>(fn), std::make_index_sequence<4>{});
     details::check_members_with_various_extents_impl(std::forward<Fn>(fn), std::make_index_sequence<8>{});
-#ifndef _PREFAST_
-    details::check_members_with_various_extents_impl(std::forward<Fn>(fn), std::make_index_sequence<16>{});
-#endif // _PREFAST_
+    if (!std::is_constant_evaluated()) {
+        details::check_members_with_various_extents_impl(std::forward<Fn>(fn), std::make_index_sequence<16>{});
+    }
 }
 
 namespace details {

diff --git a/tests/std/tests/GH_002206_unreserved_names/test.compile.pass.cpp b/tests/std/tests/GH_002206_unreserved_names/test.compile.pass.cpp
@@ -39,4 +39,4 @@
 
 #if empty_bases != 6
 #error bad macro expansion
-#endif // noop_dtor != 6
+#endif // empty_bases != 6
diff --git a/tests/std/tests/P0009R18_mdspan_extents_death/test.cpp b/tests/std/tests/P0009R18_mdspan_extents_death/test.cpp
@@ -55,7 +55,7 @@ void test_construction_from_pack_with_unrepresentable_as_index_type_values_2() {
 }
 
 void test_construction_from_pack_with_unrepresentable_as_index_type_values_3() {
-    static_assert(signed_integral<char>, "char is not signed integral");
+    static_assert(signed_integral<char>, "This test assumes that it isn't being compiled with /J");
     // Either sizeof...(exts) must be equal to 0 or each element of exts must be nonnegative and must be representable
     // as value of type index_type
     [[maybe_unused]] extents<signed char, 1, dynamic_extent> e{static_cast<char>(-1)};

diff --git a/tests/std/tests/P0009R18_mdspan_layout_left/test.cpp b/tests/std/tests/P0009R18_mdspan_layout_left/test.cpp
@@ -84,9 +84,6 @@ constexpr void check_members(const extents<IndexType, Extents...>& ext, index_se
         // Other tests are defined in 'check_construction_from_other_right_mapping' function
     }
 
-#ifdef __clang__
-    if (!is_constant_evaluated()) // FIXME clang hits constexpr limit here
-#endif
     { // Check construction from layout_stride::mapping
         array<IndexType, Ext::rank()> strides{};
         if constexpr (Ext::rank() > 0) {
@@ -261,14 +258,14 @@ constexpr void check_construction_from_other_right_mapping() {
 
 constexpr void check_construction_from_other_stride_mapping() {
     { // Check construction from layout_stride::mapping<E> with various values of E::rank()
-        static_assert(
-            is_constructible_v<layout_left::mapping<dextents<int, 0>>, layout_stride::mapping<dextents<int, 0>>>);
-        static_assert(
-            is_constructible_v<layout_left::mapping<dextents<int, 1>>, layout_stride::mapping<dextents<int, 1>>>);
-        static_assert(
-            is_constructible_v<layout_left::mapping<dextents<int, 2>>, layout_stride::mapping<dextents<int, 2>>>);
-        static_assert(
-            is_constructible_v<layout_left::mapping<dextents<int, 3>>, layout_stride::mapping<dextents<int, 3>>>);
+        static_assert(is_nothrow_constructible_v<layout_left::mapping<dextents<int, 0>>,
+            layout_stride::mapping<dextents<int, 0>>>); // strengthened
+        static_assert(is_nothrow_constructible_v<layout_left::mapping<dextents<int, 1>>,
+            layout_stride::mapping<dextents<int, 1>>>); // strengthened
+        static_assert(is_nothrow_constructible_v<layout_left::mapping<dextents<int, 2>>,
+            layout_stride::mapping<dextents<int, 2>>>); // strengthened
+        static_assert(is_nothrow_constructible_v<layout_left::mapping<dextents<int, 3>>,
+            layout_stride::mapping<dextents<int, 3>>>); // strengthened
     }
 
     { // Check construction from layout_stride::mapping<E> when E is invalid
@@ -423,10 +420,6 @@ constexpr void check_correctness() {
 #endif // ^^^ !defined(__cpp_multidimensional_subscript) ^^^
     }
 
-
-#ifdef __clang__
-    if (!is_constant_evaluated()) // FIXME clang hits constexpr limit here
-#endif
     { // 3x2 matrix with column-major order
         const array values{0, 1, 2, 3, 4, 5};
         mdspan<const int, extents<int, 3, 2>, layout_left> matrix{values.data()};
@@ -448,9 +441,6 @@ constexpr void check_correctness() {
 #endif // ^^^ !defined(__cpp_multidimensional_subscript) ^^^
     }
 
-#ifdef __clang__
-    if (!is_constant_evaluated()) // FIXME clang hits constexpr limit here
-#endif
     { // 3x2x4 tensor
         const array values{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23};
         mdspan<const int, dextents<size_t, 3>, layout_left> tensor{values.data(), 3, 2, 4};
@@ -472,9 +462,6 @@ constexpr void check_correctness() {
 #endif // ^^^ !defined(__cpp_multidimensional_subscript) ^^^
     }
 
-#ifdef __clang__
-    if (!is_constant_evaluated()) // FIXME clang hits constexpr limit here
-#endif
     { // 2x3x2x3 tensor
         const array values{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,
             26, 27, 28, 29, 30, 31, 32, 33, 34, 35};

diff --git a/tests/std/tests/P0009R18_mdspan_layout_right/test.cpp b/tests/std/tests/P0009R18_mdspan_layout_right/test.cpp
@@ -33,9 +33,6 @@ constexpr void check_members(const extents<IndexType, Extents...>& ext, index_se
     static_assert(same_as<typename Mapping::rank_type, typename Ext::rank_type>);
     static_assert(same_as<typename Mapping::layout_type, layout_right>);
 
-#ifdef __clang__
-    if (!is_constant_evaluated()) // FIXME clang hits constexpr limit here
-#endif
     { // Check default and copy constructor
         const Mapping m;
         Mapping cpy = m;
@@ -63,9 +60,6 @@ constexpr void check_members(const extents<IndexType, Extents...>& ext, index_se
     using Ext2           = extents<OtherIndexType, Extents...>;
     using Mapping2       = layout_right::mapping<Ext2>;
 
-#ifdef __clang__
-    if (!is_constant_evaluated()) // FIXME clang hits constexpr limit here
-#endif
     { // Check construction from other layout_right::mapping
         Mapping m1{ext};
         Mapping2 m2{m1};

diff --git a/tests/std/tests/P0009R18_mdspan_layout_stride_death/test.cpp b/tests/std/tests/P0009R18_mdspan_layout_stride_death/test.cpp
@@ -15,7 +15,7 @@ using namespace std;
 
 void test_default_construction() {
     using Ext = extents<signed char, dynamic_extent, 4, 5, 7>;
-    // Value of layout_right::mapping<extents_type>().required_span_size() must be
+    // Value of layout_stride::mapping<extents_type>().required_span_size() must be
     // representable as a value of type index_type
     [[maybe_unused]] layout_stride::mapping<Ext> m{}; // NB: strides are [140, 35, 7, 1]
 }