`needless_return` false positive when combined with cfg'd code afterwards

[DianaNites]

Summary

The needless_return lint does not recognize cfg'd out code located after the return, which makes the return actually required, and where removing it is invalid and will fail to compile.

Lint Name

needless_return

Reproducer

I tried this code:

fn _bar() -> u64 {
    return 456;
    
    #[cfg(no)]
    123
}

I saw this happen:

warning: unneeded `return` statement
 --> src/lib.rs:17:5
   |
17 |     return 456;
   |     ^^^^^^^^^^

I expected to see this happen:

No warning. Following the suggestion will fail to compile, and give further incorrect advice.

error: expected `;`, found `#`
  --> src/lib.rs:17:8
   |
17 |     456
   |        ^ help: add `;` here
18 |     
19 |     #[cfg(no)]
   |     - unexpected token

Version

rustc 1.87.0-nightly (1aeb99d24 2025-03-19)
binary: rustc
commit-hash: 1aeb99d248e1b0069110cb03c6f1dcc7b36fd7f3
commit-date: 2025-03-19
host: x86_64-unknown-linux-gnu
release: 1.87.0-nightly
LLVM version: 20.1.0

Additional Labels

No response