`#[ntest::timeout()]` does not work properly with C-string literals

[muzarski]

Describe the bug The macro panics when C-String literals are used in the test marked with #[ntest::timeout()].

To Reproduce Create a new crate with the following in main/lib.rs:

#[cfg(test)]
mod tests {
    #[test]
    #[ntest::timeout(100)]
    fn foo() {
        let _cstr = c"";
    }
}

Expected behavior The aforementioned code compiles.

Screenshots Here is the compiler output of cargo check --tests:

error: custom attribute panicked
 --> src/main.rs:8:5
  |
8 |     #[ntest::timeout(100)]
  |     ^^^^^^^^^^^^^^^^^^^^^^
  |
  = help: message: Unrecognized literal: `c""`

error[E0425]: cannot find function `foo` in this scope
  --> src/main.rs:9:5
   |
9  | /     fn foo() {
10 | |         let _cstr = c"";
11 | |     }
   | |_____^ not found in this scope

For more information about this error, try `rustc --explain E0425`.

Desktop (please complete the following information):

• OS: Fedora Linux
• Version: 39

Additional context What's interesting, is if the literal is hidden behind a macro_rules!, the error does not appear. Thus, the following compiles as expected:

#[cfg(test)]
mod tests {
    macro_rules! get_cstr {
        () => {
            c""
        };
    }

    #[test]
    #[ntest::timeout(100)]
    fn foo() {
        let cstr = get_cstr!();
    }
}