On Mon, Jul 7, 2025 at 11:09 AM Jonathan Wakely <jwak...@redhat.com> wrote:
> On Fri, 4 Jul 2025 at 09:30, Luc Grosheintz <luc.groshei...@gmail.com> > wrote: > > > > Previously the prerequisite of the extents ctors that > > > > static_extent(i) == dynamic_extent || extent(i) == other.extent(i). > > > > was not checked. This commit adds the __glibcxx_assert and test them. > > > > libstdc++-v3/ChangeLog: > > > > * include/std/mdspan (extents): Check prerequisite of the ctor > that > > static_extent(i) == dynamic_extent || extent(i) == > other.extent(i). > > * testsuite/23_containers/mdspan/extents/class_mandates_neg.cc: > > Test the implemented prerequisite. > > > > Signed-off-by: Luc Grosheintz <luc.groshei...@gmail.com> > > --- > > libstdc++-v3/include/std/mdspan | 13 +++++++ > > .../mdspan/extents/class_mandates_neg.cc | 2 ++ > > .../mdspan/extents/extents_mismatch_neg.cc | 35 +++++++++++++++++++ > > 3 files changed, 50 insertions(+) > > create mode 100644 > libstdc++-v3/testsuite/23_containers/mdspan/extents/extents_mismatch_neg.cc > > > > diff --git a/libstdc++-v3/include/std/mdspan > b/libstdc++-v3/include/std/mdspan > > index cf20553aaa5..1d6cdc93d80 100644 > > --- a/libstdc++-v3/include/std/mdspan > > +++ b/libstdc++-v3/include/std/mdspan > > @@ -110,10 +110,23 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION > > return __se; > > } > > > > + template<size_t _OtherRank, typename _GetOtherExtent> > > + constexpr bool > > + _S_is_compatible_extents(_GetOtherExtent __get_extent) noexcept > > Was this intended to be a static member function? > Yes, it should be. I will also adjust that locally. > > > + { > > + if constexpr (_OtherRank == _S_rank) > > + for (size_t __i = 0; __i < _S_rank; ++__i) > > + if (_Extents[__i] != dynamic_extent > > + && !cmp_equal(_Extents[__i], > _S_int_cast(__get_extent(__i)))) > > + return false; > > + return true; > > + } > > + > > template<size_t _OtherRank, typename _GetOtherExtent> > > constexpr void > > _M_init_dynamic_extents(_GetOtherExtent __get_extent) noexcept > > { > > + > __glibcxx_assert(_S_is_compatible_extents<_OtherRank>(__get_extent)); > > for (size_t __i = 0; __i < _S_rank_dynamic; ++__i) > > { > > size_t __di = __i; > > 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 f9c1c019666..67d18feda96 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 > > @@ -7,6 +7,8 @@ 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" } > > +// { dg-prune-output "non-constant condition for static assertion" } > > diff --git > a/libstdc++-v3/testsuite/23_containers/mdspan/extents/extents_mismatch_neg.cc > b/libstdc++-v3/testsuite/23_containers/mdspan/extents/extents_mismatch_neg.cc > > new file mode 100644 > > index 00000000000..b35e5310d41 > > --- /dev/null > > +++ > b/libstdc++-v3/testsuite/23_containers/mdspan/extents/extents_mismatch_neg.cc > > @@ -0,0 +1,35 @@ > > +// { dg-do compile { target c++23 } } > > +#include<mdspan> > > + > > +#include <cstdint> > > + > > +constexpr size_t dyn = std::dynamic_extent; > > + > > +constexpr bool > > +test_dyn2sta_extents_mismatch_00() > > +{ > > + auto e0 = std::extents<int, dyn>{1}; > > + [[maybe_unused]] auto e1 = std::extents<int, 2>{e0}; // { > dg-error "expansion of" } > > + return true; > > +} > > +static_assert(test_dyn2sta_extents_mismatch_00()); // { > dg-error "expansion of" } > > + > > +constexpr bool > > +test_dyn2sta_extents_mismatch_01() > > +{ > > + [[maybe_unused]] auto e = std::extents<int, 1, dyn>{2, 2}; // { > dg-error "expansion of" } > > + return true; > > +} > > +static_assert(test_dyn2sta_extents_mismatch_01()); // { > dg-error "expansion of" } > > + > > +constexpr bool > > +test_dyn2sta_extents_mismatch_02() > > +{ > > + std::array<int, 2> exts{2, 2}; > > + [[maybe_unused]] auto e = std::extents<int, 1, dyn>{exts}; // { > dg-error "expansion of" } > > + return true; > > +} > > +static_assert(test_dyn2sta_extents_mismatch_02()); // { > dg-error "expansion of" } > > + > > +// { dg-prune-output "non-constant condition for static assertion" } > > +// { dg-prune-output "__glibcxx_assert" } > > -- > > 2.49.0 > > > >