compiler-warning-level-3-c4570.md

description	title	ms.date	f1_keywords	helpviewer_keywords	ms.assetid
Learn more about: Compiler Warning (level 3) C4570	Compiler Warning (level 3) C4570	11/04/2016	C4570	C4570	feec1225-e6ad-4995-8d96-c22e864a77bd

Compiler Warning (level 3) C4570

'type' : is not explicitly declared as abstract but has abstract functions

A type that contains abstract functions should itself be marked as abstract.

Example

The following sample generates C4570.

// C4570.cpp
// compile with: /clr /W3 /c
ref struct X {   // C4570
// try the following line instead
// ref class X abstract {
   virtual void f() abstract;
};