Error: not a property - ?

[Era Scarecrow]

 This is an unexpected error; Seems it's the result of not 
down-casting a variable-type. Is this a bug? Or just need a 
better error message?

Version: DMD32 D Compiler v2.061

  struct S {
    void test(uint v) @property {}
    void test2(ulong v) @property {}
  }

  ulong x;
  S s;

  s.test2 = x;
  s.test = x;  //s.test is not a property