warning: panic message is not a string literal
   --> $DIR/lib.rs:472:12
    |
472 |     panic!(AbortNow)
    |            ^^^^^^^^
    |
    = note: `#[warn(non_fmt_panic)]` on by default
    = note: this is no longer accepted in Rust 2021
help: add a "{}" format string to Display the message
    |
472 |     panic!("{}", AbortNow)
    |            ^^^^^
help: or use std::panic::panic_any instead
    |
472 |     std::panic::panic_any(AbortNow)
    |     ^^^^^^^^^^^^^^^^^^^^^^

warning: 1 warning emitted

warning: panic message is not a string literal
   --> $DIR/lib.rs:472:12
    |
472 |     panic!(AbortNow)
    |            ^^^^^^^^
    |
    = note: `#[warn(non_fmt_panic)]` on by default
    = note: this is no longer accepted in Rust 2021
help: add a "{}" format string to Display the message
    |
472 |     panic!("{}", AbortNow)
    |            ^^^^^
help: or use std::panic::panic_any instead
    |
472 |     std::panic::panic_any(AbortNow)
    |     ^^^^^^^^^^^^^^^^^^^^^^

warning: 1 warning emitted

error: #[proc_macro_error] attribute can be used only with procedural macros

  = hint: if you are really sure that #[proc_macro_error] should be applied to this exact function, use #[proc_macro_error(allow_not_macro)]

 --> $DIR/not_proc_macro.rs:3:1
  |
3 | #[proc_macro_error]
  | ^^^^^^^^^^^^^^^^^^^
  |
  = note: this error originates in an attribute macro (in Nightly builds, run with -Z macro-backtrace for more info)