cat > bug.d << CODE
extern (C++) class RootObject
{
    bool equals(RootObject o)
    {
        return o is this;
    }

    int compare(RootObject)
    {
        assert(0);
    }

    void print()
    {
        assert(0, "Should not get called");
    }
}

void main()
{
    bool[RootObject] aa;
    aa[new RootObject] = true;
}
CODE
----
dmd -run bug
----

Because TypeInfo_Class casts every void* to a standard Object, it ends up calling the wrong vtable entries for operations like getHash.

I think we need a dedicated TypeInfo_CppClass that is similar to TypeInfo_Struct with it's xopEquals and xopHash in order to fix this bug.
C++ classes don't inherit from the common Object class, so those methods must not exist.