https://gcc.gnu.org/g:0babc6f29f7c29215674b3ee58d5dd17ce7b3849
commit r16-659-g0babc6f29f7c29215674b3ee58d5dd17ce7b3849
Author: Luc Grosheintz <luc.groshei...@gmail.com>
Date: Wed May 14 21:13:52 2025 +0200
libstdc++: Fix class mandate for extents.
The standard states that the IndexType must be a signed or unsigned
integer. This mandate was implemented using `std::is_integral_v`. Which
also includes (among others) char and bool, which neither signed nor
unsigned integers.
libstdc++-v3/ChangeLog:
* include/std/mdspan: Implement the mandate for extents as
signed or unsigned integer and not any interal type. Remove
leading underscores from names in static_assert message.
* testsuite/23_containers/mdspan/extents/class_mandates_neg.cc:
Check that extents<char,...> and extents<bool,...> are invalid.
Adjust dg-prune-output pattern.
* testsuite/23_containers/mdspan/extents/misc.cc: Update
tests to avoid `char` and `bool` as IndexType.
Reviewed-by: Tomasz Kamiński <tkami...@redhat.com>
Reviewed-by: Jonathan Wakely <jwak...@redhat.com>
Diff:
---
libstdc++-v3/include/std/mdspan | 5 +++--
.../23_containers/mdspan/extents/class_mandates_neg.cc | 12 ++++++++----
libstdc++-v3/testsuite/23_containers/mdspan/extents/misc.cc | 8 ++++----
3 files changed, 15 insertions(+), 10 deletions(-)
diff --git a/libstdc++-v3/include/std/mdspan b/libstdc++-v3/include/std/mdspan
index aee96dda7cd0..47cfa405e442 100644
--- a/libstdc++-v3/include/std/mdspan
+++ b/libstdc++-v3/include/std/mdspan
@@ -163,10 +163,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
template<typename _IndexType, size_t... _Extents>
class extents
{
- static_assert(is_integral_v<_IndexType>, "_IndexType must be integral.");
+ static_assert(__is_standard_integer<_IndexType>::value,
+ "IndexType must be a signed or unsigned integer type");
static_assert(
(__mdspan::__valid_static_extent<_Extents, _IndexType> && ...),
- "Extents must either be dynamic or representable as _IndexType");
+ "Extents must either be dynamic or representable as IndexType");
public:
using index_type = _IndexType;
diff --git
a/libstdc++-v3/testsuite/23_containers/mdspan/extents/class_mandates_neg.cc
b/libstdc++-v3/testsuite/23_containers/mdspan/extents/class_mandates_neg.cc
index b654e3920a8a..f9c1c0196669 100644
--- a/libstdc++-v3/testsuite/23_containers/mdspan/extents/class_mandates_neg.cc
+++ b/libstdc++-v3/testsuite/23_containers/mdspan/extents/class_mandates_neg.cc
@@ -1,8 +1,12 @@
// { dg-do compile { target c++23 } }
#include<mdspan>
-std::extents<char, size_t(1) << 9> e1; // { dg-error "from here" }
-std::extents<double, 1> e2; // { dg-error "from here" }
-// { dg-prune-output "dynamic or representable as _IndexType" }
-// { dg-prune-output "must be integral" }
+#include <cstdint>
+
+std::extents<uint8_t, size_t(1) << 9> e1; // { dg-error "from here" }
+std::extents<char, 1> e2; // { dg-error "from here" }
+std::extents<bool, 1> e3; // { dg-error "from here" }
+std::extents<double, 1> e4; // { dg-error "from here" }
+// { dg-prune-output "dynamic or representable as IndexType" }
+// { dg-prune-output "signed or unsigned integer" }
// { dg-prune-output "invalid use of incomplete type" }
diff --git a/libstdc++-v3/testsuite/23_containers/mdspan/extents/misc.cc
b/libstdc++-v3/testsuite/23_containers/mdspan/extents/misc.cc
index 16204aaaa75a..e71fdc542305 100644
--- a/libstdc++-v3/testsuite/23_containers/mdspan/extents/misc.cc
+++ b/libstdc++-v3/testsuite/23_containers/mdspan/extents/misc.cc
@@ -1,6 +1,7 @@
// { dg-do run { target c++23 } }
#include <mdspan>
+#include <cstdint>
#include <testsuite_hooks.h>
constexpr size_t dyn = std::dynamic_extent;
@@ -20,7 +21,6 @@ static_assert(std::is_same_v<std::extents<int, 1,
2>::rank_type, size_t>);
static_assert(std::is_unsigned_v<std::extents<int, 2>::size_type>);
static_assert(std::is_unsigned_v<std::extents<unsigned int, 2>::size_type>);
-static_assert(std::is_same_v<std::extents<char, 2>::index_type, char>);
static_assert(std::is_same_v<std::extents<int, 2>::index_type, int>);
static_assert(std::is_same_v<std::extents<unsigned int, 2>::index_type,
unsigned int>);
@@ -49,7 +49,7 @@ static_assert(check_rank_return_types<int, 1>());
// Check that the static extents don't take up space.
static_assert(sizeof(std::extents<int, 1, dyn>) == sizeof(int));
-static_assert(sizeof(std::extents<char, 1, dyn>) == sizeof(char));
+static_assert(sizeof(std::extents<short, 1, dyn>) == sizeof(short));
template<typename Extents>
class Container
@@ -58,7 +58,7 @@ class Container
[[no_unique_address]] std::extents<size_t> b0;
};
-static_assert(sizeof(Container<std::extents<char, 1, 2>>) == sizeof(int));
+static_assert(sizeof(Container<std::extents<short, 1, 2>>) == sizeof(int));
static_assert(sizeof(Container<std::extents<size_t, 1, 2>>) == sizeof(int));
// operator=
@@ -103,7 +103,7 @@ test_deduction_all()
test_deduction<0>();
test_deduction<1>(1);
test_deduction<2>(1.0, 2.0f);
- test_deduction<3>(int(1), char(2), size_t(3));
+ test_deduction<3>(int(1), short(2), size_t(3));
return true;
}
