Code shared from the Rust Playground

playground.rs

use std::alloc::{alloc, dealloc, Layout};
//use std::fmt::Pointer;

fn main() -> () {
    // Number of elements to allocate
    const NUM_ELEMENTS: usize = 100; 
    // Size of each element in bytes
    const ELEMENT_SIZE: usize = 8; // Assuming 4 bytes per element (e.g., 32-bit integer)

    // Calculate total size in bytes
    let total_size = NUM_ELEMENTS * ELEMENT_SIZE;

    // Create Layout for allocation
    let layout = Layout::from_size_align(total_size, ELEMENT_SIZE).unwrap();

    // Allocate memory using alloc()
    let ptr = unsafe { alloc(layout) };

    // Check if allocation was successful
    if ptr.is_null() {
        panic!("Allocation failed!");
    }

    // Print the memory address of the allocated block
    println!("Memory address: {:p}", ptr); 

    // Use the allocated memory (example: initialize to zero)
    unsafe {
        for i in 0..NUM_ELEMENTS {
            // Accessing elements:
            let element_ptr = ptr.add(i * ELEMENT_SIZE) as *mut i32;
            println!("{:p}", element_ptr);
            *element_ptr = 0; 
        }
    }

    // Deallocate memory using dealloc()
    unsafe { let _ = dealloc(ptr, layout); }
}