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Invalid suggestion from E0507 with & and ? #113547

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@sciguy16

Description

@sciguy16

Code

struct A {
    member: Option<String>,
}

fn main() {
    let a = A{ member: None};

    function(&a);
}

fn function(a: &A) -> Option<()> {
    let member = &a.member?;
    None
}

Current output

error[E0507]: cannot move out of `a.member` which is behind a shared reference
  --> src/main.rs:12:19
   |
12 |     let member = &a.member?;
   |                   ^^^^^^^^-
   |                   |
   |                   `a.member` moved due to this method call
   |                   move occurs because `a.member` has type `Option<String>`, which does not implement the `Copy` trait
   |
note: `branch` takes ownership of the receiver `self`, which moves `a.member`
  --> /rustc/1065d876cdbc34a872b9e17c78caaa59ea0c94d4/library/core/src/ops/try_trait.rs:217:15
help: you can `clone` the value and consume it, but this might not be your desired behavior
   |
12 |     let member = &clone().a.member?;
   |                   ++++++++

For more information about this error, try `rustc --explain E0507`.

Desired output

12 |     let member = &a.member.clone()?;

or

12 |     let member = a.member.as_ref()?;

Rationale and extra context

The suggestion for cloning the member that cannot be moved puts the clone() in the wrong place, but only (in this example) when combined with the question mark operator. Without the question mark &a.member compiles with no errors.

Playground: https://play.rust-lang.org/?version=nightly&mode=debug&edition=2021&gist=0a72b96edb6cf4f2fcab3e2cbf4c877e

Other cases

No response

Anything else?

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