C++ named requirements: StandardLayoutType (since C++11)

Specifies that a type is a standard layout type. Standard layout types are useful for communicating with code written in other programming languages.

Note: the standard doesn't define a named requirement with this name. This is a type category defined by the core language. It is included here as a named requirement only for consistency.

Requirements

The following types are collectively called standard-layout types:

• scalar types
• standard-layout class types
• arrays of such types
• cv-qualified versions of these types

Properties

See Standard-layout.

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
CWG 1672	C++11	first non-static data member rule ignored existence of empty base classes	first non-static data member rule made recursive
CWG 1813	C++11	class with a member defined in an indirect base wasn't technically standard-layout	all member declarations must be in the same class
CWG 2120	C++11	array as first member wasn't considered when comparing the first element type with type of a base	array members are considered

See also

is_standard_layout (C++11)

checks if a type is a standard-layout type (class template)