// Tests that a closure which mutates a local variable // cannot also be supplied a borrowed version of that // variable's contents. Issue #11192. struct Foo { x: isize } impl Drop for Foo { fn drop(&mut self) { println!("drop {}", self.x); } } fn main() { let mut ptr: Box<_> = Box::new(Foo { x: 0 }); let mut test = |foo: &Foo| { ptr = Box::new(Foo { x: ptr.x + 1 }); }; test(&*ptr); //~ ERROR cannot borrow `*ptr` }