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Compiler Warning (level 1) C4772

#import referenced a type from a missing type library; '__missing_type__' used as a placeholder

A type library was referenced with the #import directive. However, the type library contained a reference to another type library that was not referenced with #import. This other .tlb file was not found by the compiler.

This warning is, by default, issued as an error. C4772 can not be suppressed with /W0.

Given the following type libraries on disk created from the following two file (compiled with midl.exe):

/* c4772a.idl */
library C4772aLib
   enum E_C4772a
      one, two, three
/* c4772b.idl */
// C4772a.tlb is available when c4772b.tlb is built
library C4772bLib
   importlib ("c4772a.tlb");
   struct S_C4772b
      enum E_C4772a e;

The following sample generates C4772:

// C4772.cpp
// assumes that C4772a.tlb is not available to the compiler
// #import "C4772a.tlb"
#import "C4772b.tlb"   // C4772 uncomment previous line to resolve
                       // and make sure c4772a.tlb is on disk