Compiler Error C2594

'operator' : ambiguous conversions from 'type1' to 'type2'

No conversion from type1 to type2 was more direct than any other. We suggest two possible solutions to converting from type1 to type2. The first option is to define a direct conversion from type1 to type2, and the second option is to specify a sequence of conversions from type1 to type2.

The following sample generates C2594. The suggested resolution to the error is a sequence of conversions:

// C2594.cpp
// compile with: /c
struct A{};
struct I1 : A {};
struct I2 : A {};
struct D : I1, I2 {};

A *f (D *p) {
   return (A*) (p);    // C2594

// try the following line instead
// return static_cast<A *>(static_cast<I1 *>(p));
}