error[E0308]: mismatched types
  --> $DIR/suggest-ref-macro.rs:8:1
   |
LL | #[hello]
   | ^^^^^^^^
   | |
   | expected `&mut i32`, found integer
   | arguments to this function are incorrect
   |
note: function defined here
  --> $DIR/suggest-ref-macro.rs:8:1
   |
LL | #[hello]
   | ^^^^^^^^
   = note: this error originates in the attribute macro `hello` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0308]: mismatched types
  --> $DIR/suggest-ref-macro.rs:15:11
   |
LL |         x(123);
   |         - ^^^ expected `&mut i32`, found integer
   |         |
   |         arguments to this function are incorrect
...
LL |     bla!();
   |     ------ in this macro invocation
   |
note: function defined here
  --> $DIR/suggest-ref-macro.rs:11:4
   |
LL | fn x(_: &mut i32) {}
   |    ^ -----------
   = note: this error originates in the macro `bla` (in Nightly builds, run with -Z macro-backtrace for more info)
help: consider mutably borrowing here
   |
LL |         x(&mut 123);
   |           ++++

error[E0308]: mismatched types
  --> $DIR/suggest-ref-macro.rs:26:10
   |
LL |         x($v)
   |         - arguments to this function are incorrect
...
LL |     bla!(456);
   |          ^^^ expected `&mut i32`, found integer
   |
note: function defined here
  --> $DIR/suggest-ref-macro.rs:11:4
   |
LL | fn x(_: &mut i32) {}
   |    ^ -----------
help: consider mutably borrowing here
   |
LL |     bla!(&mut 456);
   |          ++++

error: aborting due to 3 previous errors

For more information about this error, try `rustc --explain E0308`.