cleanup, edition 2018
#![feature(asm)]
// Enable returning `!`
#![feature(never_type)]
-#[allow(unused_extern_crates)]
#[cfg(not(feature = "semihosting"))]
extern crate panic_abort;
#[cfg(feature = "semihosting")]
extern crate panic_semihosting;
-extern crate cortex_m;
-extern crate cortex_m_rt;
-extern crate stm32h7;
-
#[macro_use]
extern crate log;
