// https://issues.dlang.org/show_bug.cgi?id=20795
// REQUIRED_ARGS: -preview=dip1000
struct Foo
{
    void opEquals(T)(T rhs) if (T.init.opCast!string) {}
}
struct Bar
{
    void opEquals()(Bar)
    {
        Gun() == Foo();
    }
}
class Baz
{
    void opCast(T)() {}
}
struct Gun
{
    void[24] buff;
    auto underlying()
    {
        return cast(Baz) buff.ptr;
    }
    alias underlying this;
    void opEquals(R)(R) if (Bar.init == R.init) {}
}