Compiler Error C3241


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The latest version of this topic can be found at Compiler Error C3241.

method' : this method was not introduced by 'interface'

When you explicitly override a function, the function signature must exactly match the declaration for the function that you are overriding.

The following sample generates C3241:

// C3241.cpp  
#pragma warning(disable:4199)  
__interface IX12A {  
   void mf();  
__interface IX12B {  
   void mf(int);  
class CX12 : public IX12A, public IX12B { // C3241  
   void IX12A::mf(int);