src/test/ui/user-defined-macro-rules.stderr

error: user-defined macros may not be named `macro_rules`
  --> $DIR/user-defined-macro-rules.rs:3:1
   |
LL | macro_rules! macro_rules { () => {} } //~ ERROR user-defined macros may not be named `macro_rules`
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: aborting due to previous error