compiler-error-c3136.md

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Learn more about: Compiler Error C3136	Compiler Error C3136	10/03/2018	C3136	C3136	c77103cd-00f7-408e-b74b-4f8562039d31

Compiler Error C3136

'interface' : a COM interface can only inherit from another COM interface, 'interface' is not a COM interface

An interface to which you applied an interface attribute inherits from an interface that is not a COM interface. A COM interface ultimately inherits from IUnknown. Any interface preceded by an interface attribute is a COM interface.

The following example generates C3136:

// C3136.cpp
#include "unknwn.h"

__interface A   // C3136
// try the following line instead
// _interface A : IUnknown
{
   int a();
};

[object]
__interface B : A
{
   int aa();
};