Compiler Warning (level 1) C4096

'a': interface is not a COM interface; will not be emitted to IDL

An interface definition that you may have intended as a COM interface was not defined as a COM interface and therefore will not be emitted to the IDL file.

See Interface Attributes for a list attributes that indicate an interface is a COM interface.

The following sample generates C4096:

// C4096.cpp
// compile with: /W1 /LD
#include "windows.h"

// [object, uuid("00000000-0000-0000-0000-000000000001")]
__interface a

[coclass, uuid("00000000-0000-0000-0000-000000000002")]
struct b : a
};   // C4096, remove coclass or uncomment object

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