#[macro_export] macro_rules! foo { () => {} } #[macro_export] macro_rules! foo { () => {} } //~ ERROR the name `foo` is defined multiple times mod inner1 { #[macro_export] macro_rules! bar { () => {} } } mod inner2 { #[macro_export] macro_rules! bar { () => {} } //~ ERROR the name `bar` is defined multiple times } fn main() {}