rust/tests/ui/proc-macro/test-same-crate.stderr

error: can't use a procedural macro from the same crate that defines it
  --> $DIR/test-same-crate.rs:13:14
   |
LL |     fn t() { crate::mac!(A) }
   |              ^^^^^^^^^^
   |
   = help: you can define integration tests in a directory named `tests`

error: aborting due to 1 previous error