Category 

Type Trait Functions 

Syntax 

bool __is_trivial( typename T ) 

Returns true if and only if T is a trivial type. 

Error if T is an incomplete type. 

Trivial types are defined in Section 3.9 p10 of the Working Draft. 

Trivial classes are defined in Section 9 p5 of the Working Draft. 

Returns true if T is both const and volatile qualified. 

A type is trivial if it is:

• a scalar type
• an array of trivial types
• a class/union type where all 4 special members are trivial:
  • default constructor
  • copy constructor
  • copy assignment operator
  • destructor

Consult this online help for the definition of each __has_trivial_* traits. 

Trivial types trigger several special clauses in the standard, which may affect code generation and optimizations, or simply whether certain constructs are undefined.  

Note that trivial types are a generalization of PODs (plain old data objects) in the 2003 standard, if the POD/trivial refinement has not happened when this type function is initially implanted.