90 lines
1.6 KiB
Rust
90 lines
1.6 KiB
Rust
#![allow(mutable_borrow_reservation_conflict)]
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trait S: Sized {
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fn tpb(&mut self, _s: Self) {}
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}
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impl S for i32 {}
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fn two_phase1() {
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let mut x = 3;
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x.tpb(x);
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}
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fn two_phase2() {
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let mut v = vec![];
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v.push(v.len());
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}
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fn two_phase3(b: bool) {
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let mut x = &mut vec![];
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let mut y = vec![];
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x.push((
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{
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if b { x = &mut y };
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22
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},
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x.len(),
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));
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}
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#[allow(unreachable_code)]
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fn two_phase_raw() {
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let x: &mut Vec<i32> = &mut vec![];
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x.push(
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{
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// Unfortunately this does not trigger the problem of creating a
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// raw ponter from a pointer that had a two-phase borrow derived from
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// it because of the implicit &mut reborrow.
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let raw = x as *mut _;
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unsafe { *raw = vec![1]; }
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return
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}
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);
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}
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fn two_phase_overlapping1() {
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let mut x = vec![];
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let p = &x;
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x.push(p.len());
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}
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fn two_phase_overlapping2() {
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use std::ops::AddAssign;
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let mut x = 1;
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let l = &x;
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x.add_assign(x + *l);
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}
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fn with_interior_mutability() {
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use std::cell::Cell;
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trait Thing: Sized {
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fn do_the_thing(&mut self, _s: i32) {}
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}
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impl<T> Thing for Cell<T> {}
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let mut x = Cell::new(1);
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let l = &x;
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x
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.do_the_thing({
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x.set(3);
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l.set(4);
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x.get() + l.get()
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})
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;
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}
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fn main() {
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two_phase1();
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two_phase2();
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two_phase3(false);
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two_phase3(true);
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two_phase_raw();
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with_interior_mutability();
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two_phase_overlapping1();
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two_phase_overlapping2();
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}
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