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Compiler Warning (level 3) C4570


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The latest version of this topic can be found at 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.

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;