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Negative coverage: access_permitted_by_loan / loan is dead / premise loan_not_required_by_live_places(env, assumptions, state, loan, places_live) => state

Premise at line 902. Observed failure causes: failed_judgment.

loan is dead
LineCoverageSource
900✗(if !place_disjoint_from_place(&loan.place, &access.place))
901N/A(let places_live = places_live_for_loan(env, access, places_live_after_access))
90225(loan_not_required_by_live_places(env, assumptions, state, loan, places_live) => state)
903✗(loan_cannot_outlive_universal_regions(env, assumptions, &state.current.outlives, &loan) => ())
──────── ("loan is dead")
90524(access_permitted_by_loan(env, assumptions, state, loan, access, places_live_after_access) => state)

25 tests failed proving this premise:

Source location: tests/borrowck.rs:1792

fn foo() -> Datum {
    exists<'r0, 'r1> {
        let x: Datum = Datum { value: 0_u32 };
        let r: &'r0 Datum = &'r1 x;
        let y: Datum = x;
        return *r;
    }
}
Failed proof tree

Source location: tests/borrowck.rs:1901

fn foo() -> i32 {
    exists<'r0, 'r1> {
        let v1: i32 = 0_i32;
        let v2: &'r0 mut i32 = &mut 'r1 v1;
        // This should result in an error
        v1 = 1_i32;
        return *v2;
    }
}
Failed proof tree

Source location: tests/borrowck.rs:1939

fn foo() -> i32 {
    exists<'r0, 'r1> {
        let v1: i32 = 0_i32;
        let v2: &'r0 i32 = &'r1 v1;
        v1 = 1_i32;
        return *v2;
    }
}
Failed proof tree

Source location: tests/borrowck.rs:1989

#[test]
fn min_problem_case_3() {
    FormalityTest::new(feature_gate_program(NLL_GATE, MIN_PROBLEM_CASE_3))
        .skip_execute()
        .err(expect_test::expect![[r#"
            the rule "borrow of disjoint places" at (nll.rs) failed because
              condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
                &loan.place = *(m : &!lt_1 mut Map) : <&!lt_1 mut Map as Derefable>::Target
                &access.place = *(m : &!lt_1 mut Map) : <&!lt_1 mut Map as Derefable>::Target

            the rule "loan_cannot_outlive" at (nll.rs) failed because
              condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
                outlived_by_loan = {!lt_1, ?lt_2, ?lt_3}
                &lifetime.upcast() = !lt_1

            the rule "loan_not_required_by_universal_regions" at (nll.rs) failed because
              condition evaluated to false: `outlived_by_loan.iter().all(|p| match p
              {
                  Parameter::Ty(_) => false, Parameter::Lt(lt) => match lt.as_ref()
                  {
                      Lt::Static => false, Lt::Variable(Variable::UniversalVar(_)) => false,
                      Lt::Variable(Variable::ExistentialVar(_)) => true,
                      Lt::Variable(Variable::BoundVar(_)) =>
                      panic!("cannot outlive a bound var"), Lt::Erased => true,
                  }, Parameter::Const(_) => panic!("cannot outlive a constant"),
              })`

            the rule "write-indirect" at (nll.rs) failed because
              pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `m`

            the rule "write-indirect" at (nll.rs) failed because
              condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
                place_accessed = *(m : &!lt_1 mut Map) : <&!lt_1 mut Map as Derefable>::Target
                place_loaned_ref = m : &!lt_1 mut Map"#]]);

    FormalityTest::new(feature_gate_program(
        POLONIUS_ALPHA_GATE,
        MIN_PROBLEM_CASE_3,
    ))
    .skip_execute()
    .ok();

    FormalityTest::new(feature_gate_program(
        POLONIUS_UNLOCKED_GATE,
        MIN_PROBLEM_CASE_3,
    ))
    .skip_execute()
    .ok();
}
Failed proof tree

Source location: tests/borrowck.rs:2061

fn foo() -> i32 {
    exists<'r0, 'r1> {
        let v2: &'r0 i32;
        {
            let v1: i32 = 0_i32;
            v2 = &'r1 v1;
        }
        return *v2;
    }
}
Failed proof tree

Source location: tests/borrowck.rs:2133

fn foo() -> i32 {
    exists<'r0, 'r1> {
        let v2: &'r0 mut i32;
        {
            let v1: i32 = 0_i32;
            v2 = &mut 'r1 v1;
        }
        return *v2;
    }
}
Failed proof tree

Source location: tests/borrowck.rs:2175

fn foo() -> i32 {
    exists<'r0, 'r1> {
        let v2: &'r0 i32;
        'a: {
            let v1: i32 = 0_i32;
            v2 = &'r1 v1;
            break 'a;
        }
        return *v2;
    }
}
Failed proof tree

Source location: tests/borrowck.rs:2494

fn foo() -> i32 {
    exists<'r0, 'r1> {
        let r: &'r0 i32;
        'a: loop {
            let y: i32 = 0_i32;
            r = &'r1 y;
            continue 'a;
        }
        r; // only an error because of false edges, assumption that all loops terminate
    }
}
Failed proof tree

Source location: tests/borrowck.rs:2608

fn foo() -> i32 {
    exists<'r0, 'r1> {
        let r: &'r0 i32;
        'a: loop {
            let x: i32 = 0_i32;
            r = &'r1 x;
            break 'a;
        }
        return *r;
    }
}
Failed proof tree

Source location: tests/borrowck.rs:2735

fn foo() -> u32 {
    exists<'r0, 'r1> {
        let a: u32 = 22_u32;
        let p: &'r0 u32 = &'r1 a;
        'l: loop {
            if true {
                a = 23_u32;
                continue 'l;
            } else {
                break 'l;
            }
        }
        return *p;
    }
}
Failed proof tree

Source location: tests/borrowck.rs:2798

#[test]
fn if_false_borrowck() {
    FormalityTest::new(feature_gate_program(NLL_GATE, IF_FALSE_BORROWCK))
        .skip_execute()
        .err(expect_test::expect![[r#"
            the rule "borrow of disjoint places" at (nll.rs) failed because
              condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
                &loan.place = *(m : &!lt_1 mut Map) : <&!lt_1 mut Map as Derefable>::Target
                &access.place = *(m : &!lt_1 mut Map) : <&!lt_1 mut Map as Derefable>::Target

            the rule "loan_cannot_outlive" at (nll.rs) failed because
              condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
                outlived_by_loan = {!lt_1, ?lt_2, ?lt_3}
                &lifetime.upcast() = !lt_1

            the rule "loan_not_required_by_universal_regions" at (nll.rs) failed because
              condition evaluated to false: `outlived_by_loan.iter().all(|p| match p
              {
                  Parameter::Ty(_) => false, Parameter::Lt(lt) => match lt.as_ref()
                  {
                      Lt::Static => false, Lt::Variable(Variable::UniversalVar(_)) => false,
                      Lt::Variable(Variable::ExistentialVar(_)) => true,
                      Lt::Variable(Variable::BoundVar(_)) =>
                      panic!("cannot outlive a bound var"), Lt::Erased => true,
                  }, Parameter::Const(_) => panic!("cannot outlive a constant"),
              })`

            the rule "write-indirect" at (nll.rs) failed because
              pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `m`

            the rule "write-indirect" at (nll.rs) failed because
              condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
                place_accessed = *(m : &!lt_1 mut Map) : <&!lt_1 mut Map as Derefable>::Target
                place_loaned_ref = m : &!lt_1 mut Map"#]]);

    FormalityTest::new(feature_gate_program(POLONIUS_ALPHA_GATE, IF_FALSE_BORROWCK))
        .skip_execute()
        .ok();

    FormalityTest::new(feature_gate_program(
        POLONIUS_UNLOCKED_GATE,
        IF_FALSE_BORROWCK,
    ))
    .skip_execute()
    .ok();
}

Proof trees omitted for the remaining 15 tests.

Source location: tests/borrowck.rs:2870

fn foo() -> u32 {
    exists<'r0, 'r1, 'r2> {
        let a: u32 = 22_u32;
        let b: u32 = 22_u32;
        let p: &'r0 u32 = &'r1 a;
        a = 23_u32;
        'l: loop {
            p = &'r2 b;
            break 'l;
        }
        return *p;
    }
}

Source location: tests/borrowck.rs:3049

fn bar() -> u32 {
    exists<'r0, 'r1, 'r2> {
        let v: u32 = 0_u32;
        let p: &'r0 u32 = &'r1 v;
        let _: u32 = foo::<'r2>(&mut 'r2 v);
        return *p;
    }
}

Source location: tests/borrowck.rs:3097

fn foo() -> u32 {
    exists<'r0, 'r1> {
        let p: Point = Point { x: 0_u32, y: 0_u32 };
        let b1: &'r0 mut u32 = &mut 'r1 p.x;
        p.x = 1_u32;
        return *b1;
    }
}

Source location: tests/borrowck.rs:3131

fn foo() -> u32 {
    exists<'r0, 'r1> {
        let v1: u32 = 22_u32;
        let v2: &'r0 mut u32 = &mut 'r1 v1;
        let w: Wrapper = Wrapper { value: v1 };
        return *v2;
    }
}

Source location: tests/borrowck.rs:3168

fn foo() -> u32 {
    exists<'r0> {
        let v1: u32 = 0_u32;
        let w: Wrapper<'r0> = Wrapper::<'r0> { value: &mut 'r0 v1 };
        v1 = 1_u32;
        return *(w.value);
    }
}

Source location: tests/borrowck.rs:3230

#[test]
fn outlive_before_return_does_not_affect_merged_paths() {
    FormalityTest::new(feature_gate_program(
        NLL_GATE,
        OUTLIVE_BEFORE_RETURN_DOES_NOT_AFFECT_MERGED_PATHS,
    ))
    .skip_execute()
    .err(expect_test::expect![[r#"
        the rule "borrow of disjoint places" at (nll.rs) failed because
          condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
            &loan.place = *(a : &!lt_1 mut u8) : <&!lt_1 mut u8 as Derefable>::Target
            &access.place = *(a : &!lt_1 mut u8) : <&!lt_1 mut u8 as Derefable>::Target

        the rule "loan_cannot_outlive" at (nll.rs) failed because
          condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
            outlived_by_loan = {!lt_1, ?lt_2, ?lt_3, ?lt_4, ?lt_5}
            &lifetime.upcast() = !lt_1

        the rule "loan_not_required_by_universal_regions" at (nll.rs) failed because
          condition evaluated to false: `outlived_by_loan.iter().all(|p| match p
          {
              Parameter::Ty(_) => false, Parameter::Lt(lt) => match lt.as_ref()
              {
                  Lt::Static => false, Lt::Variable(Variable::UniversalVar(_)) => false,
                  Lt::Variable(Variable::ExistentialVar(_)) => true,
                  Lt::Variable(Variable::BoundVar(_)) =>
                  panic!("cannot outlive a bound var"), Lt::Erased => true,
              }, Parameter::Const(_) => panic!("cannot outlive a constant"),
          })`

        the rule "write-indirect" at (nll.rs) failed because
          pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `a`

        the rule "write-indirect" at (nll.rs) failed because
          condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
            place_accessed = *(a : &!lt_1 mut u8) : <&!lt_1 mut u8 as Derefable>::Target
            place_loaned_ref = a : &!lt_1 mut u8"#]]);

    FormalityTest::new(feature_gate_program(
        POLONIUS_ALPHA_GATE,
        OUTLIVE_BEFORE_RETURN_DOES_NOT_AFFECT_MERGED_PATHS,
    ))
    .skip_execute()
    .ok();

    FormalityTest::new(feature_gate_program(
        POLONIUS_UNLOCKED_GATE,
        OUTLIVE_BEFORE_RETURN_DOES_NOT_AFFECT_MERGED_PATHS,
    ))
    .skip_execute()
    .ok();
}

Source location: tests/borrowck.rs:3338

fn foo() -> u32 {
    exists<'r0, 'r1, 'r2> {
        let x: u32 = 22_u32;
        let p: &'r1 u32 = &'r0 x;
        let q: &'r2 u32 = p;
        x = 1_u32;
        q;
        return 0_u32;
    }
}

Source location: tests/borrowck.rs:3502

fn foo() -> u32 {
    exists<'r0, 'r1> {
        let x: u32 = 22_u32;
        let helper: &'r1 u32 = &'r0 x;
        x = 1_u32;
        helper;
        return 0_u32;
    }
}

Source location: tests/borrowck.rs:3751

#[test]
fn issue_63908_remove_last_node_iterative() {
    FormalityTest::new(feature_gate_program(
        NLL_GATE,
        ISSUE_63908_REMOVE_LAST_NODE_ITERATIVE,
    ))
    .skip_execute()
    .err(expect_test::expect![[r#"
        the rule "borrow of disjoint places" at (nll.rs) failed because
          condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
            &loan.place = *(cursor : &?lt_2 mut List) : <&?lt_2 mut List as Derefable>::Target
            &access.place = *(cursor : &?lt_2 mut List) : <&?lt_2 mut List as Derefable>::Target

        the rule "loan_cannot_outlive" at (nll.rs) failed because
          condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
            outlived_by_loan = {?lt_2, ?lt_3}
            &lifetime.upcast() = ?lt_2

        the rule "write-indirect" at (nll.rs) failed because
          pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `cursor`

        the rule "write-indirect" at (nll.rs) failed because
          condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
            place_accessed = *(cursor : &?lt_2 mut List) : <&?lt_2 mut List as Derefable>::Target
            place_loaned_ref = cursor : &?lt_2 mut List"#]]);

    // [polonius]: rustc errors here (known-bug #63908), same as [nll].
    FormalityTest::new(feature_gate_program(
        POLONIUS_ALPHA_GATE,
        ISSUE_63908_REMOVE_LAST_NODE_ITERATIVE,
    ))
    .skip_execute()
    .err(expect_test::expect![[r#"
        the rule "borrow of disjoint places" at (nll.rs) failed because
          condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
            &loan.place = *(cursor : &?lt_2 mut List) : <&?lt_2 mut List as Derefable>::Target
            &access.place = *(cursor : &?lt_2 mut List) : <&?lt_2 mut List as Derefable>::Target

        the rule "loan_cannot_outlive" at (nll.rs) failed because
          condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
            outlived_by_loan = {?lt_2, ?lt_3}
            &lifetime.upcast() = ?lt_2

        the rule "write-indirect" at (nll.rs) failed because
          pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `cursor`

        the rule "write-indirect" at (nll.rs) failed because
          condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
            place_accessed = *(cursor : &?lt_2 mut List) : <&?lt_2 mut List as Derefable>::Target
            place_loaned_ref = cursor : &?lt_2 mut List"#]]);

    // [legacy]: rustc passes.
    FormalityTest::new(feature_gate_program(
        POLONIUS_UNLOCKED_GATE,
        ISSUE_63908_REMOVE_LAST_NODE_ITERATIVE,
    ))
    .skip_execute()
    .ok();
}

Source location: tests/borrowck.rs:3776

#[test]
fn issue_63908_remove_last_node_iterative() {
    FormalityTest::new(feature_gate_program(
        NLL_GATE,
        ISSUE_63908_REMOVE_LAST_NODE_ITERATIVE,
    ))
    .skip_execute()
    .err(expect_test::expect![[r#"
        the rule "borrow of disjoint places" at (nll.rs) failed because
          condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
            &loan.place = *(cursor : &?lt_2 mut List) : <&?lt_2 mut List as Derefable>::Target
            &access.place = *(cursor : &?lt_2 mut List) : <&?lt_2 mut List as Derefable>::Target

        the rule "loan_cannot_outlive" at (nll.rs) failed because
          condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
            outlived_by_loan = {?lt_2, ?lt_3}
            &lifetime.upcast() = ?lt_2

        the rule "write-indirect" at (nll.rs) failed because
          pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `cursor`

        the rule "write-indirect" at (nll.rs) failed because
          condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
            place_accessed = *(cursor : &?lt_2 mut List) : <&?lt_2 mut List as Derefable>::Target
            place_loaned_ref = cursor : &?lt_2 mut List"#]]);

    // [polonius]: rustc errors here (known-bug #63908), same as [nll].
    FormalityTest::new(feature_gate_program(
        POLONIUS_ALPHA_GATE,
        ISSUE_63908_REMOVE_LAST_NODE_ITERATIVE,
    ))
    .skip_execute()
    .err(expect_test::expect![[r#"
        the rule "borrow of disjoint places" at (nll.rs) failed because
          condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
            &loan.place = *(cursor : &?lt_2 mut List) : <&?lt_2 mut List as Derefable>::Target
            &access.place = *(cursor : &?lt_2 mut List) : <&?lt_2 mut List as Derefable>::Target

        the rule "loan_cannot_outlive" at (nll.rs) failed because
          condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
            outlived_by_loan = {?lt_2, ?lt_3}
            &lifetime.upcast() = ?lt_2

        the rule "write-indirect" at (nll.rs) failed because
          pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `cursor`

        the rule "write-indirect" at (nll.rs) failed because
          condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
            place_accessed = *(cursor : &?lt_2 mut List) : <&?lt_2 mut List as Derefable>::Target
            place_loaned_ref = cursor : &?lt_2 mut List"#]]);

    // [legacy]: rustc passes.
    FormalityTest::new(feature_gate_program(
        POLONIUS_UNLOCKED_GATE,
        ISSUE_63908_REMOVE_LAST_NODE_ITERATIVE,
    ))
    .skip_execute()
    .ok();
}

Source location: tests/borrowck.rs:3917

#[test]
fn issue_57165_conditional() {
    FormalityTest::new(feature_gate_program(NLL_GATE, ISSUE_57165_CONDITIONAL))
        .skip_execute()
        .err(expect_test::expect![[r#"
            the rule "fixed-point" at (nll.rs) failed because
              condition evaluated to false: `state0 == state1`
                state0 = flow_state([scope(none, None, {}, None, [], []), scope(none, None, {}, None, [], []), scope(some(U(4)), None, {}, None, [(b, X), (p, &?lt_1 mut X)], [b : X, p : &?lt_1 mut X]), scope(some(U(4)), Some('l), {}, Some({* p}), [], [])], point_flow_state({pending_outlives(?lt_2, ?lt_1)}, {loan(?lt_2, b : X, mut)}, {}), {}, {}, {pending_outlives(?lt_2, ?lt_1)})
                state1 = flow_state([scope(none, None, {}, None, [], []), scope(none, None, {}, None, [], []), scope(some(U(4)), None, {}, None, [(b, X), (p, &?lt_1 mut X)], [b : X, p : &?lt_1 mut X]), scope(some(U(4)), Some('l), {}, Some({* p}), [], [])], point_flow_state({pending_outlives(?lt_1, ?lt_3), pending_outlives(?lt_2, ?lt_1), pending_outlives(?lt_3, ?lt_4), pending_outlives(?lt_4, ?lt_1)}, {loan(?lt_2, b : X, mut), loan(?lt_3, *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target, mut)}, {}), {labeled_flow_state('l, point_flow_state({pending_outlives(?lt_1, ?lt_3), pending_outlives(?lt_2, ?lt_1)}, {loan(?lt_2, b : X, mut), loan(?lt_3, *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target, mut)}, {}))}, {}, {pending_outlives(?lt_1, ?lt_3), pending_outlives(?lt_2, ?lt_1), pending_outlives(?lt_3, ?lt_4), pending_outlives(?lt_4, ?lt_1)})

            the rule "borrow of disjoint places" at (nll.rs) failed because
              condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
                &loan.place = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target
                &access.place = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target

            the rule "loan_cannot_outlive" at (nll.rs) failed because
              condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
                outlived_by_loan = {?lt_1, ?lt_3, ?lt_4}
                &lifetime.upcast() = ?lt_1

            the rule "write-indirect" at (nll.rs) failed because
              pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `p`

            the rule "write-indirect" at (nll.rs) failed because
              condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
                place_accessed = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target
                place_loaned_ref = p : &?lt_1 mut X

            the rule "borrow of disjoint places" at (nll.rs) failed because
              condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
                &loan.place = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target
                &access.place = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target

            the rule "loan_cannot_outlive" at (nll.rs) failed because
              condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
                outlived_by_loan = {?lt_1, ?lt_3, ?lt_4}
                &lifetime.upcast() = ?lt_1

            the rule "write-indirect" at (nll.rs) failed because
              pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `p`

            the rule "write-indirect" at (nll.rs) failed because
              condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
                place_accessed = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target
                place_loaned_ref = p : &?lt_1 mut X"#]]);

    FormalityTest::new(feature_gate_program(
        POLONIUS_ALPHA_GATE,
        ISSUE_57165_CONDITIONAL,
    ))
    .skip_execute()
    .err(expect_test::expect![[r#"
        the rule "fixed-point" at (nll.rs) failed because
          condition evaluated to false: `state0 == state1`
            state0 = flow_state([scope(none, None, {}, None, [], []), scope(none, None, {}, None, [], []), scope(some(U(4)), None, {}, None, [(b, X), (p, &?lt_1 mut X)], [b : X, p : &?lt_1 mut X]), scope(some(U(4)), Some('l), {}, Some({* p}), [], [])], point_flow_state({pending_outlives(?lt_2, ?lt_1)}, {loan(?lt_2, b : X, mut)}, {}), {}, {}, {pending_outlives(?lt_2, ?lt_1)})
            state1 = flow_state([scope(none, None, {}, None, [], []), scope(none, None, {}, None, [], []), scope(some(U(4)), None, {}, None, [(b, X), (p, &?lt_1 mut X)], [b : X, p : &?lt_1 mut X]), scope(some(U(4)), Some('l), {}, Some({* p}), [], [])], point_flow_state({pending_outlives(?lt_1, ?lt_3), pending_outlives(?lt_2, ?lt_1), pending_outlives(?lt_3, ?lt_4), pending_outlives(?lt_4, ?lt_1)}, {loan(?lt_2, b : X, mut), loan(?lt_3, *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target, mut)}, {}), {labeled_flow_state('l, point_flow_state({pending_outlives(?lt_1, ?lt_3), pending_outlives(?lt_2, ?lt_1)}, {loan(?lt_2, b : X, mut), loan(?lt_3, *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target, mut)}, {}))}, {}, {pending_outlives(?lt_1, ?lt_3), pending_outlives(?lt_2, ?lt_1), pending_outlives(?lt_3, ?lt_4), pending_outlives(?lt_4, ?lt_1)})

        the rule "borrow of disjoint places" at (nll.rs) failed because
          condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
            &loan.place = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target
            &access.place = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target

        the rule "loan_cannot_outlive" at (nll.rs) failed because
          condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
            outlived_by_loan = {?lt_1, ?lt_3, ?lt_4}
            &lifetime.upcast() = ?lt_1

        the rule "write-indirect" at (nll.rs) failed because
          pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `p`

        the rule "write-indirect" at (nll.rs) failed because
          condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
            place_accessed = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target
            place_loaned_ref = p : &?lt_1 mut X

        the rule "borrow of disjoint places" at (nll.rs) failed because
          condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
            &loan.place = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target
            &access.place = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target

        the rule "loan_cannot_outlive" at (nll.rs) failed because
          condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
            outlived_by_loan = {?lt_1, ?lt_3, ?lt_4}
            &lifetime.upcast() = ?lt_1

        the rule "write-indirect" at (nll.rs) failed because
          pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `p`

        the rule "write-indirect" at (nll.rs) failed because
          condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
            place_accessed = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target
            place_loaned_ref = p : &?lt_1 mut X"#]]);

    FormalityTest::new(feature_gate_program(
        POLONIUS_UNLOCKED_GATE,
        ISSUE_57165_CONDITIONAL,
    ))
    .skip_execute()
    .ok();
}

Source location: tests/borrowck.rs:3964

#[test]
fn issue_57165_conditional() {
    FormalityTest::new(feature_gate_program(NLL_GATE, ISSUE_57165_CONDITIONAL))
        .skip_execute()
        .err(expect_test::expect![[r#"
            the rule "fixed-point" at (nll.rs) failed because
              condition evaluated to false: `state0 == state1`
                state0 = flow_state([scope(none, None, {}, None, [], []), scope(none, None, {}, None, [], []), scope(some(U(4)), None, {}, None, [(b, X), (p, &?lt_1 mut X)], [b : X, p : &?lt_1 mut X]), scope(some(U(4)), Some('l), {}, Some({* p}), [], [])], point_flow_state({pending_outlives(?lt_2, ?lt_1)}, {loan(?lt_2, b : X, mut)}, {}), {}, {}, {pending_outlives(?lt_2, ?lt_1)})
                state1 = flow_state([scope(none, None, {}, None, [], []), scope(none, None, {}, None, [], []), scope(some(U(4)), None, {}, None, [(b, X), (p, &?lt_1 mut X)], [b : X, p : &?lt_1 mut X]), scope(some(U(4)), Some('l), {}, Some({* p}), [], [])], point_flow_state({pending_outlives(?lt_1, ?lt_3), pending_outlives(?lt_2, ?lt_1), pending_outlives(?lt_3, ?lt_4), pending_outlives(?lt_4, ?lt_1)}, {loan(?lt_2, b : X, mut), loan(?lt_3, *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target, mut)}, {}), {labeled_flow_state('l, point_flow_state({pending_outlives(?lt_1, ?lt_3), pending_outlives(?lt_2, ?lt_1)}, {loan(?lt_2, b : X, mut), loan(?lt_3, *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target, mut)}, {}))}, {}, {pending_outlives(?lt_1, ?lt_3), pending_outlives(?lt_2, ?lt_1), pending_outlives(?lt_3, ?lt_4), pending_outlives(?lt_4, ?lt_1)})

            the rule "borrow of disjoint places" at (nll.rs) failed because
              condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
                &loan.place = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target
                &access.place = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target

            the rule "loan_cannot_outlive" at (nll.rs) failed because
              condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
                outlived_by_loan = {?lt_1, ?lt_3, ?lt_4}
                &lifetime.upcast() = ?lt_1

            the rule "write-indirect" at (nll.rs) failed because
              pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `p`

            the rule "write-indirect" at (nll.rs) failed because
              condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
                place_accessed = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target
                place_loaned_ref = p : &?lt_1 mut X

            the rule "borrow of disjoint places" at (nll.rs) failed because
              condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
                &loan.place = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target
                &access.place = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target

            the rule "loan_cannot_outlive" at (nll.rs) failed because
              condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
                outlived_by_loan = {?lt_1, ?lt_3, ?lt_4}
                &lifetime.upcast() = ?lt_1

            the rule "write-indirect" at (nll.rs) failed because
              pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `p`

            the rule "write-indirect" at (nll.rs) failed because
              condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
                place_accessed = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target
                place_loaned_ref = p : &?lt_1 mut X"#]]);

    FormalityTest::new(feature_gate_program(
        POLONIUS_ALPHA_GATE,
        ISSUE_57165_CONDITIONAL,
    ))
    .skip_execute()
    .err(expect_test::expect![[r#"
        the rule "fixed-point" at (nll.rs) failed because
          condition evaluated to false: `state0 == state1`
            state0 = flow_state([scope(none, None, {}, None, [], []), scope(none, None, {}, None, [], []), scope(some(U(4)), None, {}, None, [(b, X), (p, &?lt_1 mut X)], [b : X, p : &?lt_1 mut X]), scope(some(U(4)), Some('l), {}, Some({* p}), [], [])], point_flow_state({pending_outlives(?lt_2, ?lt_1)}, {loan(?lt_2, b : X, mut)}, {}), {}, {}, {pending_outlives(?lt_2, ?lt_1)})
            state1 = flow_state([scope(none, None, {}, None, [], []), scope(none, None, {}, None, [], []), scope(some(U(4)), None, {}, None, [(b, X), (p, &?lt_1 mut X)], [b : X, p : &?lt_1 mut X]), scope(some(U(4)), Some('l), {}, Some({* p}), [], [])], point_flow_state({pending_outlives(?lt_1, ?lt_3), pending_outlives(?lt_2, ?lt_1), pending_outlives(?lt_3, ?lt_4), pending_outlives(?lt_4, ?lt_1)}, {loan(?lt_2, b : X, mut), loan(?lt_3, *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target, mut)}, {}), {labeled_flow_state('l, point_flow_state({pending_outlives(?lt_1, ?lt_3), pending_outlives(?lt_2, ?lt_1)}, {loan(?lt_2, b : X, mut), loan(?lt_3, *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target, mut)}, {}))}, {}, {pending_outlives(?lt_1, ?lt_3), pending_outlives(?lt_2, ?lt_1), pending_outlives(?lt_3, ?lt_4), pending_outlives(?lt_4, ?lt_1)})

        the rule "borrow of disjoint places" at (nll.rs) failed because
          condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
            &loan.place = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target
            &access.place = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target

        the rule "loan_cannot_outlive" at (nll.rs) failed because
          condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
            outlived_by_loan = {?lt_1, ?lt_3, ?lt_4}
            &lifetime.upcast() = ?lt_1

        the rule "write-indirect" at (nll.rs) failed because
          pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `p`

        the rule "write-indirect" at (nll.rs) failed because
          condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
            place_accessed = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target
            place_loaned_ref = p : &?lt_1 mut X

        the rule "borrow of disjoint places" at (nll.rs) failed because
          condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
            &loan.place = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target
            &access.place = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target

        the rule "loan_cannot_outlive" at (nll.rs) failed because
          condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
            outlived_by_loan = {?lt_1, ?lt_3, ?lt_4}
            &lifetime.upcast() = ?lt_1

        the rule "write-indirect" at (nll.rs) failed because
          pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `p`

        the rule "write-indirect" at (nll.rs) failed because
          condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
            place_accessed = *(p : &?lt_1 mut X) : <&?lt_1 mut X as Derefable>::Target
            place_loaned_ref = p : &?lt_1 mut X"#]]);

    FormalityTest::new(feature_gate_program(
        POLONIUS_UNLOCKED_GATE,
        ISSUE_57165_CONDITIONAL,
    ))
    .skip_execute()
    .ok();
}

Source location: tests/borrowck.rs:4316

#[test]
fn issue_46859_decoder_next() {
    // [nll]: rustc errors
    FormalityTest::new(feature_gate_program(NLL_GATE, ISSUE_46859_DECODER_NEXT))
        .skip_execute()
        .err(expect_test::expect![[r#"
            the rule "fixed-point" at (nll.rs) failed because
              condition evaluated to false: `state0 == state1`
                state0 = flow_state([scope(some(U(1)), None, {}, None, [(d, &!lt_1 mut Decoder)], [d : &!lt_1 mut Decoder]), scope(some(U(1)), None, {}, None, [], []), scope(some(U(3)), None, {}, None, [], []), scope(some(U(3)), Some('l), {}, Some({(* d) . buf_read}), [], [])], point_flow_state({pending_outlives(!lt_1, ?lt_2), pending_outlives(?lt_2, ?lt_3), pending_outlives(?lt_3, !lt_1)}, {}, {}), {}, {}, {pending_outlives(!lt_1, ?lt_2), pending_outlives(?lt_2, ?lt_3), pending_outlives(?lt_3, !lt_1)})
                state1 = flow_state([scope(some(U(1)), None, {}, None, [(d, &!lt_1 mut Decoder)], [d : &!lt_1 mut Decoder]), scope(some(U(1)), None, {}, None, [], []), scope(some(U(3)), None, {}, None, [], []), scope(some(U(3)), Some('l), {}, Some({(* d) . buf_read}), [], [])], point_flow_state({pending_outlives(!lt_1, ?lt_2), pending_outlives(?lt_2, ?lt_3), pending_outlives(?lt_3, !lt_1)}, {loan(?lt_2, *(d : &!lt_1 mut Decoder) : <&!lt_1 mut Decoder as Derefable>::Target . buf_read[Decoder , struct] : u32, mut)}, {}), {}, {}, {pending_outlives(!lt_1, ?lt_2), pending_outlives(?lt_2, ?lt_3), pending_outlives(?lt_3, !lt_1)})

            the rule "borrow of disjoint places" at (nll.rs) failed because
              condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
                &loan.place = *(d : &!lt_1 mut Decoder) : <&!lt_1 mut Decoder as Derefable>::Target . buf_read[Decoder , struct] : u32
                &access.place = *(d : &!lt_1 mut Decoder) : <&!lt_1 mut Decoder as Derefable>::Target . buf_read[Decoder , struct] : u32

            the rule "loan_cannot_outlive" at (nll.rs) failed because
              condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
                outlived_by_loan = {!lt_1, ?lt_2, ?lt_3}
                &lifetime.upcast() = !lt_1

            the rule "loan_not_required_by_universal_regions" at (nll.rs) failed because
              condition evaluated to false: `outlived_by_loan.iter().all(|p| match p
              {
                  Parameter::Ty(_) => false, Parameter::Lt(lt) => match lt.as_ref()
                  {
                      Lt::Static => false, Lt::Variable(Variable::UniversalVar(_)) => false,
                      Lt::Variable(Variable::ExistentialVar(_)) => true,
                      Lt::Variable(Variable::BoundVar(_)) =>
                      panic!("cannot outlive a bound var"), Lt::Erased => true,
                  }, Parameter::Const(_) => panic!("cannot outlive a constant"),
              })`

            the rule "write-indirect" at (nll.rs) failed because
              pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `*(d : &!lt_1 mut Decoder) : <&!lt_1 mut Decoder as Derefable>::Target . buf_read[Decoder , struct]`

            the rule "write-indirect" at (nll.rs) failed because
              pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `d`

            the rule "write-indirect" at (nll.rs) failed because
              condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
                place_accessed = *(d : &!lt_1 mut Decoder) : <&!lt_1 mut Decoder as Derefable>::Target . buf_read[Decoder , struct] : u32
                place_loaned_ref = d : &!lt_1 mut Decoder

            the rule "borrow of disjoint places" at (nll.rs) failed because
              condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
                &loan.place = *(d : &!lt_1 mut Decoder) : <&!lt_1 mut Decoder as Derefable>::Target . buf_read[Decoder , struct] : u32
                &access.place = *(d : &!lt_1 mut Decoder) : <&!lt_1 mut Decoder as Derefable>::Target . buf_read[Decoder , struct] : u32

            the rule "loan_cannot_outlive" at (nll.rs) failed because
              condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
                outlived_by_loan = {!lt_1, ?lt_2, ?lt_3}
                &lifetime.upcast() = !lt_1

            the rule "loan_not_required_by_universal_regions" at (nll.rs) failed because
              condition evaluated to false: `outlived_by_loan.iter().all(|p| match p
              {
                  Parameter::Ty(_) => false, Parameter::Lt(lt) => match lt.as_ref()
                  {
                      Lt::Static => false, Lt::Variable(Variable::UniversalVar(_)) => false,
                      Lt::Variable(Variable::ExistentialVar(_)) => true,
                      Lt::Variable(Variable::BoundVar(_)) =>
                      panic!("cannot outlive a bound var"), Lt::Erased => true,
                  }, Parameter::Const(_) => panic!("cannot outlive a constant"),
              })`

            the rule "write-indirect" at (nll.rs) failed because
              pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `*(d : &!lt_1 mut Decoder) : <&!lt_1 mut Decoder as Derefable>::Target . buf_read[Decoder , struct]`

            the rule "write-indirect" at (nll.rs) failed because
              pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `d`

            the rule "write-indirect" at (nll.rs) failed because
              condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
                place_accessed = *(d : &!lt_1 mut Decoder) : <&!lt_1 mut Decoder as Derefable>::Target . buf_read[Decoder , struct] : u32
                place_loaned_ref = d : &!lt_1 mut Decoder"#]]);

    // [polonius]: rustc passes
    FormalityTest::new(feature_gate_program(
        POLONIUS_ALPHA_GATE,
        ISSUE_46859_DECODER_NEXT,
    ))
    .skip_execute()
    .ok();

    // [legacy]: rustc passes
    FormalityTest::new(feature_gate_program(
        POLONIUS_UNLOCKED_GATE,
        ISSUE_46859_DECODER_NEXT,
    ))
    .skip_execute()
    .ok();
}

Source location: tests/borrowck.rs:4458

#[test]
fn issue_92985_filtering_lending_iterator() {
    // [nll]: rustc errors
    FormalityTest::new(feature_gate_program(NLL_GATE, ISSUE_92985_FILTER_NEXT))
        .skip_execute()
        .err(expect_test::expect![[r#"
            the rule "fixed-point" at (nll.rs) failed because
              condition evaluated to false: `state0 == state1`
                state0 = flow_state([scope(some(U(1)), None, {}, None, [(f, &!lt_1 mut Filter)], [f : &!lt_1 mut Filter]), scope(some(U(1)), None, {}, None, [], []), scope(some(U(4)), None, {}, None, [], []), scope(some(U(4)), Some('l), {}, Some({(* f) . iter, (* f) . predicate}), [], [])], point_flow_state({pending_outlives(!lt_1, ?lt_2), pending_outlives(!lt_1, ?lt_3), pending_outlives(?lt_2, !lt_1), pending_outlives(?lt_2, ?lt_4)}, {}, {}), {}, {}, {pending_outlives(!lt_1, ?lt_2), pending_outlives(!lt_1, ?lt_3), pending_outlives(?lt_2, !lt_1), pending_outlives(?lt_2, ?lt_4)})
                state1 = flow_state([scope(some(U(1)), None, {}, None, [(f, &!lt_1 mut Filter)], [f : &!lt_1 mut Filter]), scope(some(U(1)), None, {}, None, [], []), scope(some(U(4)), None, {}, None, [], []), scope(some(U(4)), Some('l), {}, Some({(* f) . iter, (* f) . predicate}), [], [])], point_flow_state({pending_outlives(!lt_1, ?lt_2), pending_outlives(!lt_1, ?lt_3), pending_outlives(?lt_2, !lt_1), pending_outlives(?lt_2, ?lt_4)}, {loan(?lt_2, *(f : &!lt_1 mut Filter) : <&!lt_1 mut Filter as Derefable>::Target . iter[Filter , struct] : u32, mut), loan(?lt_3, *(f : &!lt_1 mut Filter) : <&!lt_1 mut Filter as Derefable>::Target . predicate[Filter , struct] : u32, mut)}, {}), {labeled_flow_state('l, point_flow_state({pending_outlives(!lt_1, ?lt_2), pending_outlives(!lt_1, ?lt_3), pending_outlives(?lt_2, !lt_1), pending_outlives(?lt_2, ?lt_4)}, {loan(?lt_2, *(f : &!lt_1 mut Filter) : <&!lt_1 mut Filter as Derefable>::Target . iter[Filter , struct] : u32, mut)}, {}))}, {}, {pending_outlives(!lt_1, ?lt_2), pending_outlives(!lt_1, ?lt_3), pending_outlives(?lt_2, !lt_1), pending_outlives(?lt_2, ?lt_4)})

            the rule "borrow of disjoint places" at (nll.rs) failed because
              condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
                &loan.place = *(f : &!lt_1 mut Filter) : <&!lt_1 mut Filter as Derefable>::Target . iter[Filter , struct] : u32
                &access.place = *(f : &!lt_1 mut Filter) : <&!lt_1 mut Filter as Derefable>::Target . iter[Filter , struct] : u32

            the rule "loan_cannot_outlive" at (nll.rs) failed because
              condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
                outlived_by_loan = {!lt_1, ?lt_2, ?lt_3, ?lt_4}
                &lifetime.upcast() = !lt_1

            the rule "loan_not_required_by_universal_regions" at (nll.rs) failed because
              condition evaluated to false: `outlived_by_loan.iter().all(|p| match p
              {
                  Parameter::Ty(_) => false, Parameter::Lt(lt) => match lt.as_ref()
                  {
                      Lt::Static => false, Lt::Variable(Variable::UniversalVar(_)) => false,
                      Lt::Variable(Variable::ExistentialVar(_)) => true,
                      Lt::Variable(Variable::BoundVar(_)) =>
                      panic!("cannot outlive a bound var"), Lt::Erased => true,
                  }, Parameter::Const(_) => panic!("cannot outlive a constant"),
              })`

            the rule "write-indirect" at (nll.rs) failed because
              pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `*(f : &!lt_1 mut Filter) : <&!lt_1 mut Filter as Derefable>::Target . iter[Filter , struct]`

            the rule "write-indirect" at (nll.rs) failed because
              pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `f`

            the rule "write-indirect" at (nll.rs) failed because
              condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
                place_accessed = *(f : &!lt_1 mut Filter) : <&!lt_1 mut Filter as Derefable>::Target . iter[Filter , struct] : u32
                place_loaned_ref = f : &!lt_1 mut Filter

            the rule "borrow of disjoint places" at (nll.rs) failed because
              condition evaluated to false: `place_disjoint_from_place(&loan.place, &access.place)`
                &loan.place = *(f : &!lt_1 mut Filter) : <&!lt_1 mut Filter as Derefable>::Target . iter[Filter , struct] : u32
                &access.place = *(f : &!lt_1 mut Filter) : <&!lt_1 mut Filter as Derefable>::Target . iter[Filter , struct] : u32

            the rule "loan_cannot_outlive" at (nll.rs) failed because
              condition evaluated to false: `!outlived_by_loan.contains(&lifetime.upcast())`
                outlived_by_loan = {!lt_1, ?lt_2, ?lt_3, ?lt_4}
                &lifetime.upcast() = !lt_1

            the rule "loan_not_required_by_universal_regions" at (nll.rs) failed because
              condition evaluated to false: `outlived_by_loan.iter().all(|p| match p
              {
                  Parameter::Ty(_) => false, Parameter::Lt(lt) => match lt.as_ref()
                  {
                      Lt::Static => false, Lt::Variable(Variable::UniversalVar(_)) => false,
                      Lt::Variable(Variable::ExistentialVar(_)) => true,
                      Lt::Variable(Variable::BoundVar(_)) =>
                      panic!("cannot outlive a bound var"), Lt::Erased => true,
                  }, Parameter::Const(_) => panic!("cannot outlive a constant"),
              })`

            the rule "write-indirect" at (nll.rs) failed because
              pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `*(f : &!lt_1 mut Filter) : <&!lt_1 mut Filter as Derefable>::Target . iter[Filter , struct]`

            the rule "write-indirect" at (nll.rs) failed because
              pattern `TypedPlaceExpressionData::Deref(place_loaned_ref)` did not match value `f`

            the rule "write-indirect" at (nll.rs) failed because
              condition evaluated to false: `place_accessed.is_prefix_of(place_loaned_ref)`
                place_accessed = *(f : &!lt_1 mut Filter) : <&!lt_1 mut Filter as Derefable>::Target . iter[Filter , struct] : u32
                place_loaned_ref = f : &!lt_1 mut Filter"#]]);

    // [polonius]: rustc passes
    FormalityTest::new(feature_gate_program(
        POLONIUS_ALPHA_GATE,
        ISSUE_92985_FILTER_NEXT,
    ))
    .skip_execute()
    .ok();

    // [legacy]: rustc passes
    FormalityTest::new(feature_gate_program(
        POLONIUS_UNLOCKED_GATE,
        ISSUE_92985_FILTER_NEXT,
    ))
    .skip_execute()
    .ok();
}