Fix build: Use the new rust asm! available in rustc 1.63.0-nightly

src/interrupt.rs

@@ -2,6 +2,7 @@
 
 use core::prelude::v1::*;
 use core::marker::PhantomData;
+use core::arch::asm;
 
 /// Helper struct that automatically restores interrupts
 /// on drop.
@@ -22,15 +23,15 @@ pub fn without_interrupts<F, T>(f: F) -> T
 impl DisableInterrupts {
     #[inline(always)]
     pub fn new() -> DisableInterrupts {
-        unsafe { llvm_asm!("CLI") }
+        unsafe { asm!("cli") }
         DisableInterrupts(PhantomData)
     }
 }
 
 impl Drop for DisableInterrupts {
     #[inline(always)]
     fn drop(&mut self) {
-        unsafe { llvm_asm!("SEI") }
+        unsafe { asm!("sei") }
     }
 }
 

src/lib.rs

@@ -1,10 +1,8 @@
 //! Definitions of register addresses and bits within those registers
 
-#![feature(llvm_asm)]
-#![feature(const_fn)]
+#![feature(asm_experimental_arch)]
 #![feature(associated_type_defaults)]
 #![feature(lang_items)]
-#![feature(unwind_attributes)]
 #![feature(proc_macro_hygiene)]
 
 #![no_std]