Type inference failing

I tried this code:

fn foo() -> Option<Box<u8>> {
    todo!()
}

fn bar(_: Option<&u8>) {}

fn main() {
    let mut v = vec![];
    bar(v.last().map(|x| &**x));
    v.push(foo());
}

I would expect v to have a knowable type but it's failing with this error:

error[E0282]: type annotations needed for `&T`
  --> src/main.rs:11:27
   |
11 |         bar(v.last().map(|x| &**x));
   |                           ^   --- type must be known at this point
   |
help: consider giving this closure parameter an explicit type, where the type for type parameter `T` is specified
   |
11 |         bar(v.last().map(|x: &T| &**x));
   |                            ++++

For more information about this error, try `rustc --explain E0282`.
error: could not compile `tests` (bin "tests") due to 1 previous error

It's able to infer it if we swap the lines

    v.push(foo());
    bar(v.last().map(|x| &**x));

Meta

Tried on nightly and stable

Start by compiling the reproduction in src/main.rs and compare the two statement orderings shown in the report. Investigate Rust's type-inference behavior around v.last(), map, and the later push call. Done means the reported ordering infers v's type without an annotation and has regression coverage.