diff options
Diffstat (limited to 'src/span.h')
| -rw-r--r-- | src/span.h | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/src/span.h b/src/span.h index 78c30fa553..d5d7ebccc4 100644 --- a/src/span.h +++ b/src/span.h @@ -18,6 +18,16 @@ #define ASSERT_IF_DEBUG(x) #endif +#if defined(__clang__) +#if __has_attribute(lifetimebound) +#define SPAN_ATTR_LIFETIMEBOUND [[clang::lifetimebound]] +#else +#define SPAN_ATTR_LIFETIMEBOUND +#endif +#else +#define SPAN_ATTR_LIFETIMEBOUND +#endif + /** A Span is an object that can refer to a contiguous sequence of objects. * * It implements a subset of C++20's std::span. @@ -87,14 +97,14 @@ public: * Note that this restriction does not exist when converting arrays or other Spans (see above). */ template <typename V> - constexpr Span(V& other, + constexpr Span(V& other SPAN_ATTR_LIFETIMEBOUND, typename std::enable_if<!is_Span<V>::value && std::is_convertible<typename std::remove_pointer<decltype(std::declval<V&>().data())>::type (*)[], C (*)[]>::value && std::is_convertible<decltype(std::declval<V&>().size()), std::size_t>::value, std::nullptr_t>::type = nullptr) : m_data(other.data()), m_size(other.size()){} template <typename V> - constexpr Span(const V& other, + constexpr Span(const V& other SPAN_ATTR_LIFETIMEBOUND, typename std::enable_if<!is_Span<V>::value && std::is_convertible<typename std::remove_pointer<decltype(std::declval<const V&>().data())>::type (*)[], C (*)[]>::value && std::is_convertible<decltype(std::declval<const V&>().size()), std::size_t>::value, std::nullptr_t>::type = nullptr) @@ -154,9 +164,9 @@ public: /** MakeSpan for arrays: */ template <typename A, int N> Span<A> constexpr MakeSpan(A (&a)[N]) { return Span<A>(a, N); } /** MakeSpan for temporaries / rvalue references, only supporting const output. */ -template <typename V> constexpr auto MakeSpan(V&& v) -> typename std::enable_if<!std::is_lvalue_reference<V>::value, Span<const typename std::remove_pointer<decltype(v.data())>::type>>::type { return std::forward<V>(v); } +template <typename V> constexpr auto MakeSpan(V&& v SPAN_ATTR_LIFETIMEBOUND) -> typename std::enable_if<!std::is_lvalue_reference<V>::value, Span<const typename std::remove_pointer<decltype(v.data())>::type>>::type { return std::forward<V>(v); } /** MakeSpan for (lvalue) references, supporting mutable output. */ -template <typename V> constexpr auto MakeSpan(V& v) -> Span<typename std::remove_pointer<decltype(v.data())>::type> { return v; } +template <typename V> constexpr auto MakeSpan(V& v SPAN_ATTR_LIFETIMEBOUND) -> Span<typename std::remove_pointer<decltype(v.data())>::type> { return v; } /** Pop the last element off a span, and return a reference to that element. */ template <typename T> |