message: Gate no_std on target_os = "none"
diff: #![feature(drain_filter)]
  #![feature(strict_provenance)]
  #![feature(is_some_and)]
  -#![no_std]
  +#![cfg_attr(target_os = "none", no_std)]
  #![cfg_attr(target_os = "none", feature(custom_test_frameworks))]
  #![cfg_attr(all(target_os = "none", test), test_runner(crate::test_runner))]
  #![cfg_attr(
  