src/test/ui/traits/trait-impl-method-mismatch.rs

   1 trait Mumbo {
   2     fn jumbo(&self, x: &usize) -> usize;
   3 }
   4
   5 impl Mumbo for usize {
   6     // Cannot have a larger effect than the trait:
   7     unsafe fn jumbo(&self, x: &usize) { *self + *x; }
   8     //~^ ERROR method `jumbo` has an incompatible type for trait
   9     //~| expected fn pointer `fn
  10     //~| found fn pointer `unsafe fn
  11 }
  12
  13 fn main() {}