Thread Local Add

thread_local_add.rs

use core::cell::RefCell;

macro_rules! call {
  ( $FUNCTION:ident $ARGS:expr => $RETURN:ident) => {
    unsafe { $FUNCTION::LOCAL.set(Funct { args: $ARGS, ret: &mut $RETURN }) }
    $FUNCTION();
  };
}

fn main() -> std::process::ExitCode
{
  let mut val = 0;
  call!(add(5,4)=>val);
  std::println!("{}", val);

  std::process::ExitCode::SUCCESS
}

pub mod add {
  use super::*;
  thread_local! {
    pub static LOCAL : RefCell <Funct<(i32,i32),*mut i32>> = RefCell::new( Funct{args : (0,0), ret : core::ptr::null_mut()});
  }
}
fn add() {
  unsafe {
    add::LOCAL.with_borrow_mut(|l| {
      *l.ret = l.args.0 + l.args.1;
    })
  }
}
struct Funct<A, R> {
  args: A,
  ret: R,
}
struct AddArgs {
  l: i32,
  r: i32,
}