Cargo afl takes Cargo path during installation and if cargo path changes, the returned error is not obvious

[Disconnect3d]

I may be wrong, but it seems to me that:

1. cargo install afl takes/saves full cargo path during its installation
2. When we execute cargo afl ... it uses a saved cargo path (from an envvar in

   afl.rs/src/bin/cargo-afl.rs

   Line 294 in aad1eec

    let cargo_path = env!("CARGO"); 

   ?)
3. If the cargo path changed between 1) and our actual fuzzing attempt, things go wrong and we panic on unwrap here:

   afl.rs/src/bin/cargo-afl.rs

   Lines 349 to 357 in aad1eec

    let status = Command::new(cargo_path) 
        .arg(subcommand) 
        .args(args) 
        .env("RUSTFLAGS", &rustflags) 
        .env("RUSTDOCFLAGS", &rustdocflags) 
        .env("ASAN_OPTIONS", asan_options) 
        .env("TSAN_OPTIONS", tsan_options) 
        .status() 
        .unwrap(); 

With an error like:

thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: Os { code: 2, kind: NotFound, message: "No such file or directory" }', /Users/dc/.cargo/registry/src/github.com-1ecc6299db9ec823/afl-0.10.0/src/bin/cargo-afl.rs:357:10
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

This occured for me when I used afl via test-fuzz and I don't have all the steps necessary to reproduce this. However, my cargo installation comes from nix package manager and I think I maybe updated cargo via nix? (or maybe it is related to rust toolchain changes?)

All this was fixed after I reinstalled afl via cargo install afl --force.

So it would be nice to either fix this, or, show an error that cargo install afl --force may fix it.