src/test/ui/borrowck/borrowck-assign-to-andmut-in-borrowed-loc.rs

   1 // Test that assignments to an `&mut` pointer which is found in a
   2 // borrowed (but otherwise non-aliasable) location is illegal.
   3
   4 struct S<'a> {
   5     pointer: &'a mut isize
   6 }
   7
   8 fn copy_borrowed_ptr<'a>(p: &'a mut S<'a>) -> S<'a> {
   9     S { pointer: &mut *p.pointer }
  10 }
  11
  12 fn main() {
  13     let mut x = 1;
  14
  15     {
  16         let mut y = S { pointer: &mut x };
  17         let z = copy_borrowed_ptr(&mut y);
  18         *y.pointer += 1;
  19         //~^ ERROR cannot use `*y.pointer`
  20         //~| ERROR cannot assign to `*y.pointer`
  21         *z.pointer += 1;
  22     }
  23 }