error: user-defined macros may not be named `macro_rules` --> $DIR/user-defined-macro-rules.rs:13:1 | LL | macro_rules! macro_rules { () => {} } //~ ERROR user-defined macros may not be named `macro_rules` | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error[E0601]: `main` function not found in crate `user_defined_macro_rules` | = note: consider adding a `main` function to `$DIR/user-defined-macro-rules.rs` error: aborting due to 2 previous errors For more information about this error, try `rustc --explain E0601`.