LUB coercions works for a function but fails for a closure

I tried the following code (playground), following the examples for LUB coercion in the Reference, chapter 10.7.

The closure does not compile

    let clo = || {
        if true {
            let x: *mut i32 = &mut 1;
            x
        } else if false {
            let x: &i32 = &1;
            x
        } else {
            let x: &mut i32 = &mut 1;
            x
        }
    };
    let _: *const i32 = clo();

with the error:

error[E0308]: `if` and `else` have incompatible types

A similar function does compile:

fn f() -> *const i32 {
    if true {
        let x: *mut i32 = &mut 1;
        x
    } else if false {
        let x: &i32 = &1;
        x
    } else {
        let x: &mut i32 = &mut 1;
        x
    }
}

According to the Reference, I expected that either both the closure and the function compiles or neither of them.

Start by compiling the closure and function examples from the issue in the linked Rust Playground, then compare their LUB coercion behavior with the Reference's type-coercion examples. Trace the compiler's handling of closure return types and conditional expressions. Done means the behavior matches the documented rules, with an appropriate regression test for the reproduced case.