EXTERN_SYM_PTR

rustubs

Macro EXTERN_SYM_PTR 

Source 
macro_rules! EXTERN_SYM_PTR {
    ($vis:vis $name:ident ,  $ext:ident) => { ... };
    ($vis:vis $name:ident : $ty:ty = $ext:ident) => { ... };
}
Expand description

macro to declare a external symbol: cast its address into e.g. u64. useful for getting the address of a tag in asm.

tag:
    // something

EXTERN_SYM_PTR!(_TAG, tag)

becomes

extern "C" {
   fn tag();
}
const TAG: *const () = tag as *const ();