#![feature(plugin)] #![plugin(clippy)] fn x(y: &i32) -> i32 { *y } #[deny(clippy)] #[allow(unused_variables)] fn main() { let a = 5; let b = x(&a); let c = x(&&a); //~ ERROR: this expression borrows a reference that is immediately dereferenced by the compiler let s = &String::from("hi"); let s_ident = f(&s); // should not error, because `&String` implements Copy, but `String` does not let g_val = g(&Vec::new()); // should not error, because `&Vec` derefs to `&[T]` let vec = Vec::new(); let vec_val = g(&vec); // should not error, because `&Vec` derefs to `&[T]` h(&"foo"); // should not error, because the `&&str` is required, due to `&Trait` } fn f(y: &T) -> T { *y } fn g(y: &[u8]) -> u8 { y[0] } trait Trait {} impl<'a> Trait for &'a str {} fn h(_: &Trait) {}