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|
note: no external requirements
--> $DIR/propagate-approximated-shorter-to-static-comparing-against-free.rs:21:15
|
LL | foo(cell, |cell_a, cell_x| {
| ^^^^^^^^^^^^^^^^
|
= note: defining type: case1::{closure#0} with closure args [
i32,
for<Region(BrAnon)> extern "rust-call" fn((std::cell::Cell<&'?1 u32>, std::cell::Cell<&'^0 u32>)),
(),
]
= note: late-bound region is '?2
error[E0521]: borrowed data escapes outside of closure
--> $DIR/propagate-approximated-shorter-to-static-comparing-against-free.rs:22:9
|
LL | foo(cell, |cell_a, cell_x| {
| ------ ------ `cell_x` is a reference that is only valid in the closure body
| |
| `cell_a` declared here, outside of the closure body
LL | cell_a.set(cell_x.get()); // forces 'x: 'a, error in closure
| ^^^^^^^^^^^^^^^^^^^^^^^^ `cell_x` escapes the closure body here
|
= note: requirement occurs because of the type `Cell<&'?9 u32>`, which makes the generic argument `&'?9 u32` invariant
= note: the struct `Cell<T>` is invariant over the parameter `T`
= help: see <https://doc.rust-lang.org/nomicon/subtyping.html> for more information about variance
note: no external requirements
--> $DIR/propagate-approximated-shorter-to-static-comparing-against-free.rs:18:1
|
LL | fn case1() {
| ^^^^^^^^^^
|
= note: defining type: case1
note: external requirements
--> $DIR/propagate-approximated-shorter-to-static-comparing-against-free.rs:35:15
|
LL | foo(cell, |cell_a, cell_x| {
| ^^^^^^^^^^^^^^^^
|
= note: defining type: case2::{closure#0} with closure args [
i32,
for<Region(BrAnon)> extern "rust-call" fn((std::cell::Cell<&'?1 u32>, std::cell::Cell<&'^0 u32>)),
(),
]
= note: late-bound region is '?2
= note: number of external vids: 2
= note: where '?1: '?0
note: no external requirements
--> $DIR/propagate-approximated-shorter-to-static-comparing-against-free.rs:28:1
|
LL | fn case2() {
| ^^^^^^^^^^
|
= note: defining type: case2
error[E0597]: `a` does not live long enough
--> $DIR/propagate-approximated-shorter-to-static-comparing-against-free.rs:30:26
|
LL | let a = 0;
| - binding `a` declared here
LL | let cell = Cell::new(&a);
| ^^ borrowed value does not live long enough
...
LL | cell_x.set(cell_a.get()); // forces 'a: 'x, implies 'a = 'static -> borrow error
| ------------------------ argument requires that `a` is borrowed for `'static`
LL | })
LL | }
| - `a` dropped here while still borrowed
|
note: requirement that the value outlives `'static` introduced here
--> $DIR/propagate-approximated-shorter-to-static-comparing-against-free.rs:13:8
|
LL | F: for<'x> FnOnce(Cell<&'a u32>, Cell<&'x u32>),
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: aborting due to 2 previous errors
Some errors have detailed explanations: E0521, E0597.
For more information about an error, try `rustc --explain E0521`.
|
