Compiler Error C2154

'type': only enumeration type is allowed as an argument to compiler intrinsic type trait '__underlying_type'

Remarks

You can only get the underlying type of an enumeration type.

Example

The following example generates C2154:

// C2154.cpp
// compile with: /c

struct S {};
enum E {};
enum class EC {};

__underlying_type(S) s;     // C2154
__underlying_type(int) i;   // C2154
__underlying_type(E) e;     // OK
__underlying_type(EC) ec;   // OK

See also

underlying_type class