//@ aux-build:two_macros.rs //@ compile-flags:--extern non_existent mod n { extern crate two_macros; } mod m { fn check() { two_macros::m!(); //~ ERROR failed to resolve: use of undeclared crate or module `two_macros` } } macro_rules! define_std_as_non_existent { () => { extern crate std as non_existent; //~^ ERROR `extern crate` items cannot shadow names passed with `--extern` } } define_std_as_non_existent!(); fn main() {}