Alternatively-named main function `use`d as `main` marked as dead code

[Omnikar]

Code

// Marked as dead code despite being used as main
fn different_main() {
    println!("Hello from different_main");
}
use different_main as main;

Current output

warning: function `different_main` is never used
 --> src/main.rs:2:4
  |
2 | fn different_main() {
  |    ^^^^^^^^^^^^^^
  |
  = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default

Desired output

No warning

Rationale and extra context

I am not sure exactly why, but the warning shows up when checking via cargo check --all-targets and not with cargo check.

Other cases

Rust Version

rustc 1.96.0 (ac68faa20 2026-05-25)
binary: rustc
commit-hash: ac68faa20c58cbccd01ee7208bf3b6e93a7d7f96
commit-date: 2026-05-25
host: aarch64-apple-darwin
release: 1.96.0
LLVM version: 22.1.2

Anything else?

No response

[bjorn3]

Looks like this only shows up when --test is passed to rustc.

[MaximilianAzendorf]

@rustbot claim