compiler-warning-c4694.md

description	title	ms.date	f1_keywords	helpviewer_keywords	ms.assetid
Learn more about: Compiler Warning C4694	Compiler Warning C4694	10/25/2017	C4694	C4694	5ca122bb-34f3-43ee-a21f-95802cd515f7

Compiler Warning C4694

'class': a sealed abstract class cannot have a base-class 'base_class'

An abstract and sealed class cannot inherit from a reference type; a sealed and abstract class can neither implement the base class functions nor allow itself to be used as a base class.

For more information, see abstract, sealed, and Classes and Structs.

This warning is automatically promoted to an error. If you wish to modify this behavior, use #pragma warning.

Example

The following sample generates C4694.

// C4694.cpp
// compile with: /c /clr
ref struct A {};
ref struct B sealed abstract : A {};   // C4694