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Negative coverage: borrow_check_statement / exists / premise borrow_check_block(env, assumptions_body, state, block, places_live_on_exit) => state

Premise at line 327. Observed failure causes: failed_judgment.

exists
LineCoverageSource
322✗(if !feature_gate_enabled_in_program(&env.program, &FeatureGateName::PoloniusUnlocked) && !feature_gate_enabled_in_program(&env.program, &FeatureGateName::PoloniusAlpha))
324N/A(let (env, subst, block) = env.instantiate_existentially(binder))
325N/A(let assumptions_body = (assumptions, wf_assumptions_for_existential_subst(&subst)))
326N/A(let entry_state = state.clone())
32723(borrow_check_block(env, assumptions_body, state, block, places_live_on_exit) => state)
329N/A(let state = entry_state.with_global_outlives_from(&state))
3306(borrow_check_block(env, assumptions_body, state, block, places_live_on_exit) => state)
331N/A(let state = state.pop_subst(&env.env, subst))
──────── ("exists")
33354(borrow_check_statement(env, assumptions, state, Stmt::Exists { binder }, places_live_on_exit) => (env, state))

23 tests failed proving this premise:

Source location: tests/borrowck.rs:473

fn foo() -> Datum {
    exists<'r0, 'r1> {
        let x: Datum = Datum { value: 0_u32 };
        let r: &'r0 Datum = &'r1 x;
        let y: Datum = *r;
        return y;
    }
}
Failed proof tree
… (200 of 1236 nodes shown)

Source location: tests/borrowck.rs:1132

fn foo() -> Datum {
    exists<'r0, 'r1> {
        let x: Datum = Datum { value: 0_u32 };
        let r: &'r0 mut Datum = &mut 'r1 x;
        let y: Datum = *r;
        return y;
    }
}
Failed proof tree
… (200 of 1236 nodes shown)

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: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:2234

fn foo<'a, 'b>(v1: &'a u32) -> &'b u32 {
    exists<'r0> {
        let v2: &'r0 u32 = v1;
        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:2541

fn foo() -> i32 {
    exists<'r0, 'r1> {
        let x: i32 = 0_i32;
        let r: &'r0 i32;
        'a: loop {
            r; // this *may* read from `y` in a previous iteration
            let y: i32 = 0_i32;
            r = &'r1 y;
            continue 'a;
        }
    }
}

Proof trees omitted for the remaining 13 tests.

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;
    }
}

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;
    }
}

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: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: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:4651

#[test]
fn flow_sensitive_invariance_use_both() {
    FormalityTest::new(feature_gate_program(
        NLL_GATE,
        FLOW_SENSITIVE_INVARIANCE_USE_BOTH,
    ))
    .skip_execute()
    .err(expect_test::expect![[r#"
        crates/formality-rust/src/prove/prove_via.rs:8:1: no applicable rules for prove_via { goal: !lt_1 : !lt_2, via: @ wf(?lt_0), assumptions: {@ wf(?lt_0)}, env: Env { variables: [!lt_1, !lt_2, ?lt_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_outlives.rs:8:1: no applicable rules for prove_outlives { a: !lt_1, b: !lt_2, assumptions: {@ wf(?lt_0)}, env: Env { variables: [!lt_1, !lt_2, ?lt_0], bias: Soundness, pending: [], allow_pending_outlives: false } }"#]]);

    FormalityTest::new(feature_gate_program(
        POLONIUS_ALPHA_GATE,
        FLOW_SENSITIVE_INVARIANCE_USE_BOTH,
    ))
    .skip_execute()
    .err(expect_test::expect![[r#"
        crates/formality-rust/src/prove/prove_via.rs:8:1: no applicable rules for prove_via { goal: !lt_1 : !lt_2, via: @ wf(?lt_0), assumptions: {@ wf(?lt_0)}, env: Env { variables: [!lt_1, !lt_2, ?lt_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_outlives.rs:8:1: no applicable rules for prove_outlives { a: !lt_1, b: !lt_2, assumptions: {@ wf(?lt_0)}, env: Env { variables: [!lt_1, !lt_2, ?lt_0], bias: Soundness, pending: [], allow_pending_outlives: false } }"#]]);

    FormalityTest::new(feature_gate_program(
        POLONIUS_UNLOCKED_GATE,
        FLOW_SENSITIVE_INVARIANCE_USE_BOTH,
    ))
    .skip_execute()
    .err(expect_test::expect![[r#"
        crates/formality-rust/src/prove/prove_via.rs:8:1: no applicable rules for prove_via { goal: !lt_1 : !lt_2, via: @ wf(?lt_0), assumptions: {@ wf(?lt_0)}, env: Env { variables: [!lt_1, !lt_2, ?lt_0], bias: Soundness, pending: [], allow_pending_outlives: false } }

        crates/formality-rust/src/prove/prove_outlives.rs:8:1: no applicable rules for prove_outlives { a: !lt_1, b: !lt_2, assumptions: {@ wf(?lt_0)}, env: Env { variables: [!lt_1, !lt_2, ?lt_0], bias: Soundness, pending: [], allow_pending_outlives: false } }"#]]);
}