#![no_main]
#![no_std]
extern crate cortex_m_rt;
extern crate panic_halt;
use cortex_m_rt::{entry, pre_init};
#[pre_init]
unsafe fn foo(undef: i32) {}
//~^ ERROR `#[pre_init]` function must have signature `unsafe fn()`
#[entry]
fn bar() -> ! {
loop {}
}