Adjust some more code that was depending on the function and delegate calling conventions being equal. There's also an instance in `tango.text.convert.Layout` that should be adjusted: {{{ Index: tango/text/convert/Layout.d =================================================================== --- tango/text/convert/Layout.d (revision 4578) +++ tango/text/convert/Layout.d (working copy) -660,8 +660,12 @@ case TypeCode.STRUCT: auto s = cast(TypeInfo_Struct) type; - if (s.xtoString) - return Utf.fromString8 (s.xtoString(p), result); + if (s.xtoString) { + char[] delegate() toString; + toString.ptr = p; + toString.funcptr = cast(char[] function()) s.xtoString; + return Utf.fromString8 (toString(), result); + } goto default; case TypeCode.INTERFACE: }}}

module interface5;

extern(C) int printf(char*,...);

interface I
{
    void func();
}

class C : I
{
    int i;
    void func()
    {
        printf("C\n");
        i++;
    }
}

void main()
{
    C c = new C;
    c.func();
    {
        I i = c;
        i.func();

        C c2 = cast(C)i;
        c2.func();

        c.func();
        assert(c.i == 4);
    }
}