'class::member' is ambiguous
The specified member was derived from more than one object.
This error is caused by referencing a member of an object that was inherited from more than one object. Make the member unambiguous by providing a cast or by changing the name of the offending members of the base classes.
Warning C4385 is generated in conjunction with this error and provides additional information about the ambiguity.
The following is an example of this error:
struct A { int x; };
struct B { int x; };
struct C : A, B {};
void func ()
{
C aC;
aC.x = 9; // error
}