How to pass `--cfg` to mirai?

[AiDaiP]

Issue

In my project, I need to use --cfg to build. I tried using RUSTFLAGS or config.toml to pass --cfg, which works for cargo build but does not work for cargo mirai

Steps to Reproduce

pub mod my_mod{
    #[cfg(my_cfg)]
    fn func1(){}

    fn func2(){
        func1()
    }
}

./.cargo/config.toml

[build]
rustflags = ["--cfg", "my_cfg"]

[target.x86_64-unknown-linux-gnu]
rustflags = ["--cfg", "my_cfg"]

cargo mirai

or

RUSTFLAGS="--cfg=my_cfg" cargo mirai

Expected Behavior

It should be same ascargo build without any errors.

Actual Results

error[E0425]: cannot find function `func1` in this scope
 --> src/lib.rs:6:9
  |
6 |         func1()
  |         ^^^^^ not found in this scope

For more information about this error, try `rustc --explain E0425`.
error: could not compile `timing_channels` (lib) due to previous error

Environment

rustc --version
rustc 1.70.0 (90c541806 2023-05-31)

[Herman Venter]

This seems like a bug. You can probably work around it for now as follows:
MIRAI_FLAGS="-- --cfg=my_cfg" cargo mirai