compiler/rustc_error_codes/src/error_codes/E0734.md

   1 A stability attribute has been used outside of the standard library.
   2
   3 Erroneous code example:
   4
   5 ```compile_fail,E0734
   6 #[rustc_deprecated(since = "b", reason = "text")] // invalid
   7 #[stable(feature = "a", since = "b")] // invalid
   8 #[unstable(feature = "b", issue = "none")] // invalid
   9 fn foo(){}
  10 ```
  11
  12 These attributes are meant to only be used by the standard library and are
  13 rejected in your own crates.