Migrate build system to 2024 edition

Author: GuillaumeGomez

build_system/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "y"
 version = "0.1.0"
-edition = "2021"
+edition = "2024"
 
 [dependencies]
 boml = "0.3.1"

build_system/src/main.rs

@@ -60,7 +60,9 @@ pub enum Command {
 
 fn main() {
     if env::var("RUST_BACKTRACE").is_err() {
-        env::set_var("RUST_BACKTRACE", "1");
+        unsafe {
+            env::set_var("RUST_BACKTRACE", "1");
+        }
     }
 
     let command = match env::args().nth(1).as_deref() {

build_system/src/utils.rs

@@ -10,7 +10,7 @@ use std::path::{Path, PathBuf};
 use std::process::{Command, ExitStatus, Output};
 
 #[cfg(unix)]
-extern "C" {
+unsafe extern "C" {
     fn raise(signal: c_int) -> c_int;
 }