tests/ui/generator/dropck.rs

   1 #![feature(generators, generator_trait)]
   2
   3 use std::cell::RefCell;
   4 use std::ops::Generator;
   5 use std::pin::Pin;
   6
   7 fn main() {
   8     let (mut gen, cell);
   9     cell = Box::new(RefCell::new(0));
  10     let ref_ = Box::leak(Box::new(Some(cell.borrow_mut())));
  11     //~^ ERROR `*cell` does not live long enough [E0597]
  12     // the upvar is the non-dropck `&mut Option<Ref<'a, i32>>`.
  13     gen = || {
  14         // but the generator can use it to drop a `Ref<'a, i32>`.
  15         let _d = ref_.take(); //~ ERROR `ref_` does not live long enough
  16         yield;
  17     };
  18     Pin::new(&mut gen).resume(());
  19     // drops the RefCell and then the Ref, leading to use-after-free
  20 }