public static unsafe void TestSized4096CopyToStackAlloc0(ref Sized4096 a, ref Sized4096 b)
        {
            Sized4096 *c = stackalloc Sized4096[1];

            (&c->First)[4] = 42;
            a = *c;
        }
        public static unsafe void TestSized4096CopyToStackAlloc1(ref Sized4096 a, ref Sized4096 b)
        {
            byte *     bytes = stackalloc byte[4096];
            Sized4096 *c     = (Sized4096 *)bytes;

            (&c->First)[4] = 42;
            a = *c;
        }