tmp/tmpeyna7y_u/{from.md → to.md}
RENAMED
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The header `<type_traits>` has the following addition:
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``` cpp
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namespace std {
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template<class T> struct is_pod;
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template<class T> constexpr bool is_pod_v = is_pod<T>::value;
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template<size_t Len, size_t Align = default-alignment> // see below
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struct aligned_storage;
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template<size_t Len, size_t Align = default-alignment> // see below
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-
using aligned_storage_t =
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template<size_t Len, class... Types>
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struct aligned_union;
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template<size_t Len, class... Types>
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using aligned_union_t =
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}
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```
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The behavior of a program that adds specializations for any of the
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templates defined in this subclause is undefined, unless explicitly
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permitted by the specification of the corresponding template.
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-
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-
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```
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*
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-
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-
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-
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-
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standard-layout class, and has no non-static data members of type
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non-POD class (or array thereof). A POD type is a scalar type, a POD
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class, an array of such a type, or a cv-qualified version of one of
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these types.
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[*Note 1*: It is unspecified whether a closure
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type [[expr.prim.lambda.closure]] is a POD type. — *end note*]
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``` cpp
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template<size_t Len, size_t Align = default-alignment>
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struct aligned_storage;
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@@ -53,15 +80,15 @@ type `T` or to *default-alignment*.
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The member typedef `type` denotes a trivial standard-layout type
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suitable for use as uninitialized storage for any object whose size is
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at most `Len` and whose alignment is a divisor of `Align`.
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[*Note
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by an array `std::byte[Len]` declared with
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`alignas(Align)`. — *end note*]
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[*Note
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A typical implementation would define `aligned_storage` as:
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``` cpp
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template<size_t Len, size_t Alignment>
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The header `<type_traits>` has the following addition:
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``` cpp
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namespace std {
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template<class T> struct is_trivial;
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template<class T> constexpr bool is_trivial_v = is_trivial<T>::value;
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template<class T> struct is_pod;
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template<class T> constexpr bool is_pod_v = is_pod<T>::value;
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template<size_t Len, size_t Align = default-alignment> // see below
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struct aligned_storage;
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template<size_t Len, size_t Align = default-alignment> // see below
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using aligned_storage_t = aligned_storage<Len, Align>::type;
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template<size_t Len, class... Types>
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struct aligned_union;
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template<size_t Len, class... Types>
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using aligned_union_t = aligned_union<Len, Types...>::type;
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}
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```
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The behavior of a program that adds specializations for any of the
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templates defined in this subclause is undefined, unless explicitly
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permitted by the specification of the corresponding template.
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A *trivial class* is a class that is trivially copyable and has one or
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more eligible default constructors, all of which are trivial.
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[*Note 1*: In particular, a trivial class does not have virtual
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functions or virtual base classes. — *end note*]
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A *trivial type* is a scalar type, a trivial class, an array of such a
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type, or a cv-qualified version of one of these types.
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A *POD class* is a class that is both a trivial class and a
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standard-layout class, and has no non-static data members of type
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non-POD class (or array thereof). A *POD type* is a scalar type, a POD
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class, an array of such a type, or a cv-qualified version of one of
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these types.
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``` cpp
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template<class T> struct is_trivial;
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```
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*Preconditions:* `remove_all_extents_t<T>` shall be a complete type or
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cv `void`.
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*Remarks:* `is_trivial<T>` is a *Cpp17UnaryTypeTrait*[[meta.rqmts]] with
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a base characteristic of `true_type` if `T` is a trivial type, and
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`false_type` otherwise.
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[*Note 1*: It is unspecified whether a closure
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type [[expr.prim.lambda.closure]] is a trivial type. — *end note*]
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``` cpp
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template<class T> struct is_pod;
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```
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*Preconditions:* `remove_all_extents_t<T>` shall be a complete type or
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cv `void`.
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*Remarks:* `is_pod<T>` is a *Cpp17UnaryTypeTrait*[[meta.rqmts]] with a
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base characteristic of `true_type` if `T` is a POD type, and
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`false_type` otherwise.
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[*Note 2*: It is unspecified whether a closure
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type [[expr.prim.lambda.closure]] is a POD type. — *end note*]
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``` cpp
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template<size_t Len, size_t Align = default-alignment>
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struct aligned_storage;
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The member typedef `type` denotes a trivial standard-layout type
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suitable for use as uninitialized storage for any object whose size is
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at most `Len` and whose alignment is a divisor of `Align`.
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[*Note 3*: Uses of `aligned_storage<Len, Align>::type` can be replaced
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by an array `std::byte[Len]` declared with
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`alignas(Align)`. — *end note*]
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[*Note 4*:
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A typical implementation would define `aligned_storage` as:
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``` cpp
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template<size_t Len, size_t Alignment>
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