Rustでmalloc, free

use std::alloc::{alloc, dealloc, Layout};
use std::ptr;

fn main() {
    unsafe {
        let layout = Layout::new::<i32>();
        let ptr = alloc(layout) as *mut i32;

        if ptr.is_null() {
            panic!("メモリ確保に失敗しました");
        }

        *ptr = 42;
        println!("ptrが指す値: {}", *ptr);

        dealloc(ptr as *mut u8, layout);
    }
}

Finished `dev` profile [unoptimized + debuginfo] target(s) in 1.83s
Running `target/debug/memory`
ptrが指す値: 42