public static unsafe void TestFixed4096CopyToStackAlloc0(ref Fixed4096 a, ref Fixed4096 b)
        {
            Fixed4096 *c = stackalloc Fixed4096[1];

            c->First[4] = 42;
            a           = *c;
        }
        public static unsafe void TestFixed4096CopyToStackAlloc1(ref Fixed4096 a, ref Fixed4096 b)
        {
            byte *     bytes = stackalloc byte[4096];
            Fixed4096 *c     = (Fixed4096 *)bytes;

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