Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Avoid use of zero-length carray #336

Merged
merged 1 commit into from
Jun 3, 2024
Merged

Avoid use of zero-length carray #336

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
20 changes: 16 additions & 4 deletions include/experimental/__p0009_bits/layout_stride.hpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -202,9 +202,17 @@ struct layout_stride {
return __strides_storage_t{static_cast<index_type>(s[Idxs])...};
}

template<class IntegralType>
MDSPAN_TEMPLATE_REQUIRES(
class IntegralType,
// The is_convertible condition is added to make sfinae valid
// the extents_type::rank() > 0 is added to avoid use of non-standard zero length c-array
(std::is_convertible<IntegralType, typename extents_type::index_type>::value && (extents_type::rank() > 0))
)
MDSPAN_INLINE_FUNCTION
static constexpr const __strides_storage_t fill_strides(mdspan_non_standard_tag, const IntegralType (&s)[extents_type::rank()]) {
// despite the requirement some compilers still complain about zero length array during parsing
// making it length 1 now, but since the thing can't be instantiated due to requirement the actual
// instantiation of strides_storage will not fail despite mismatching length
static constexpr const __strides_storage_t fill_strides(mdspan_non_standard_tag, const IntegralType (&s)[extents_type::rank()>0?extents_type::rank():1]) {
return __strides_storage_t{static_cast<index_type>(s[Idxs])...};
}

Expand Down Expand Up @@ -325,15 +333,19 @@ struct layout_stride {
// MSVC 19.32 does not like using index_type here, requires the typename Extents::index_type
// error C2641: cannot deduce template arguments for 'MDSPAN_IMPL_STANDARD_NAMESPACE::layout_stride::mapping'
_MDSPAN_TRAIT(std::is_convertible, const std::remove_const_t<IntegralTypes>&, typename Extents::index_type) &&
_MDSPAN_TRAIT(std::is_nothrow_constructible, typename Extents::index_type, const std::remove_const_t<IntegralTypes>&)
_MDSPAN_TRAIT(std::is_nothrow_constructible, typename Extents::index_type, const std::remove_const_t<IntegralTypes>&) &&
(Extents::rank() > 0)
)
)
MDSPAN_INLINE_FUNCTION
constexpr
mapping(
mdspan_non_standard_tag,
extents_type const& e,
IntegralTypes (&s)[extents_type::rank()]
// despite the requirement some compilers still complain about zero length array during parsing
// making it length 1 now, but since the thing can't be instantiated due to requirement the actual
// instantiation of strides_storage will not fail despite mismatching length
IntegralTypes (&s)[extents_type::rank()>0?extents_type::rank():1]
) noexcept
#if defined(_MDSPAN_USE_ATTRIBUTE_NO_UNIQUE_ADDRESS)
: __members{
Expand Down
Loading