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fn borrow_mut<T>(x: &mut T) -> &mut T { x }
fn borrow<T>(x: &T) -> &T { x }
fn borrow_mut2<T>(_: &mut T, _: &mut T) {}
fn borrow2<T>(_: &mut T, _: &T) {}
fn double_mut_borrow<T>(x: &mut Box<T>) {
let y = borrow_mut(x);
let z = borrow_mut(x);
//~^ ERROR cannot borrow `*x` as mutable more than once at a time
drop((y, z));
}
fn double_imm_borrow(x: &mut Box<i32>) {
let y = borrow(x);
let z = borrow(x);
**x += 1;
//~^ ERROR cannot assign to `**x` because it is borrowed
drop((y, z));
}
fn double_mut_borrow2<T>(x: &mut Box<T>) {
borrow_mut2(x, x);
//~^ ERROR cannot borrow `*x` as mutable more than once at a time
}
fn double_borrow2<T>(x: &mut Box<T>) {
borrow2(x, x);
//~^ ERROR cannot borrow `*x` as mutable because it is also borrowed as immutable
}
pub fn main() {}
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