// Test that attempt to mutably borrow `&mut` pointer while pointee is // borrowed yields an error. // // Example from compiler/rustc_borrowck/borrowck/README.md fn foo<'a>(mut t0: &'a mut isize, mut t1: &'a mut isize) { let p: &isize = &*t0; // Freezes `*t0` let mut t2 = &mut t0; //~ ERROR cannot borrow `t0` **t2 += 1; // Mutates `*t0` p.use_ref(); } fn bar<'a>(mut t0: &'a mut isize, mut t1: &'a mut isize) { let p: &mut isize = &mut *t0; // Claims `*t0` let mut t2 = &mut t0; //~ ERROR cannot borrow `t0` **t2 += 1; // Mutates `*t0` but not through `*p` p.use_mut(); } fn main() { } trait Fake { fn use_mut(&mut self) { } fn use_ref(&self) { } } impl<T> Fake for T { }