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Negative coverage: access_permitted_by_loan / write-indirect / premise if place_accessed.is_prefix_of(place_loaned_ref)

Premise at line 884. Observed failure causes: if_false.

write-indirect
LineCoverageSource
881(place_loaned in place_loaned.all_prefixes())
88221(if let TypedPlaceExpressionData::Deref(place_loaned_ref) = place_loaned.data())
883(prove_ty_is_ref(env, assumptions, state, &place_loaned_ref.ty) => state)
8847(if place_accessed.is_prefix_of(place_loaned_ref))
──────── ("write-indirect")
8869(access_permitted_by_loan(
env,
assumptions,
state,
Loan { lt: _, place: place_loaned, kind: _ },
Access { kind: AccessKind::Write, place: place_accessed },
_live_places,
) => state)

7 tests failed proving this premise:


Source location: tests/borrowck.rs:2158 (all coverage from this test)

fn min_problem_case_3<'a>(m: &'a mut Map) -> &'a mut Map {
    exists<'r0, 'r1> {
        let n: &'r0 mut Map = &'r0 mut *m;
        if true {
            return n;
        } else {
            let o: &'r1 mut Map = &'r1 mut *m;
            return o;
        }
    }
}
Failed proof tree

Source location: tests/borrowck.rs:2960 (all coverage from this test)

fn foo<'a>(m: &'a mut Map) -> &'a mut Map {
    exists<'r0, 'r1> {
        let n: &'r0 mut Map = &'r0 mut *m;
        if false {
            return n;
        } else {
            let o: &'r1 mut Map = &'r1 mut *m;
            return o;
        }
    }
}
Failed proof tree

Source location: tests/borrowck.rs:3387 (all coverage from this test)

fn reborrow<'a>(a: &'a mut u8) -> &'a mut u8 {
    exists<'r0, 'r1, 'r2, 'r3> {
        // This creates an outlives constraint
        let b: &'r1 mut u8 = &'r0 mut *a;
        if true {
            return b;
        } else {
            // this means the loan remains live
        }

        // If the outlives constraint propagated here,
        // we would get an error.
        let c: &'r3 mut u8 = &'r2 mut *a;
        return c;
    }
}
Failed proof tree

Source location: tests/borrowck.rs:3855 (all coverage from this test)

fn remove_last_node_iterative<'a>(node: &'a mut List) -> u32 {
    exists<'r0, 'r1> {
        let cursor: &'r0 mut List = &'r0 mut *node;
        'l: loop {
            let next: &'r1 mut List = &'r1 mut *cursor;
            if true {
                cursor = next;
            } else {
                break 'l;
            }
        }
        *cursor = List { value: 0_u32 };
        return 0_u32;
    }
}
Failed proof tree

Source location: tests/borrowck.rs:3967 (all coverage from this test)

fn conditional() -> u32 {
    exists<'r0, 'r1, 'r2, 'r3> {
        let b: X = X { value: 0_u32 };
        let p: &'r0 mut X = &'r1 mut b;
        'l: loop {
            let now: &'r2 mut X = &'r2 mut *p;
            if true {
                if true {
                    let next: &'r3 mut X = next_of::<'r3>(&'r3 mut *now);
                    p = next;
                } else {
                }
            } else {
                break 'l;
            }
        }
        return 0_u32;
    }
}
Failed proof tree

Source location: tests/borrowck.rs:4233 (all coverage from this test)

fn next<'a>(d: &'a mut Decoder) -> &'a u32 {
    exists<'r0, 'r1> {
        'l: loop {
            let buf: &'r0 u32 = fill_buf::<'r0>(&'r0 mut (*d).buf_read);
            let s: &'r1 u32 = decode::<'r1>(buf);
            if true {
                return s;
            } else {
            }
        }
    }
}
Failed proof tree

Source location: tests/borrowck.rs:4356 (all coverage from this test)

fn next<'s>(f: &'s mut Filter) -> &'s mut u32 {
    exists<'r0, 'r1, 'r2> {
        'l: loop {
            let item: &'r0 mut u32 = iter_next::<'r0>(&'r0 mut (*f).iter);
            if true {
                let keep: bool = call_predicate::<'r1, 'r2>(&'r1 mut (*f).predicate, &'r2 *item);
                if keep {
                    return item;
                } else {
                }
            } else {
                break 'l;
            }
        }
        return no_item::<'s>();
    }
}
Failed proof tree