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Compiler Warning (level 1) C4929

'file': typelibrary contains a union; ignoring the 'embedded_idl' qualifier

The embedded_idl attribute of #import could not be applied to the type library because a union is present in the type library. To resolve this warning, don't use embedded_idl.

The following scenario generates C4929:

// C4929a.cpp
// compile with: /LD /W1
#include <objbase.h>
[module(name="Test")];
[public, switch_type(short)] typedef union _TD_UNION_TYPE   {
   [case(24)]
      float fM;
   [case(25)]
      double dMN;
   [default]
      int x;
} TD_UNION_TYPE;

[export, public] typedef struct _TDW_TYPE {
   [switch_is(sU)] TD_UNION_TYPE w;
      short sU;
} TD_TYPE;

[object, uuid("00000000-0000-0000-0000-000000000001")]
__interface I {
   HRESULT f(TD_TYPE*);
};

[coclass, uuid("00000000-0000-0000-0000-000000000002")]
struct C : I {
   HRESULT f(TD_TYPE*) { return 0; }
};
// C4929b.cpp
// compile with: /W1 /c
#import " C4929a.dll" embedded_idl   // C4929
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