1 // SPDX-License-Identifier: Apache-2.0 OR MIT 2 3 use pin_init::*; 4 5 // Struct with size over 1GiB 6 #[derive(Debug)] 7 #[allow(dead_code)] 8 pub struct BigStruct { 9 buf: [u8; 1024 * 1024 * 1024], 10 a: u64, 11 b: u64, 12 c: u64, 13 d: u64, 14 managed_buf: ManagedBuf, 15 } 16 17 #[derive(Debug)] 18 pub struct ManagedBuf { 19 buf: [u8; 1024 * 1024], 20 } 21 22 impl ManagedBuf { 23 pub fn new() -> impl Init<Self> { 24 init!(ManagedBuf { buf <- init_zeroed() }) 25 } 26 } 27 28 fn main() { 29 #[cfg(any(feature = "std", feature = "alloc"))] 30 { 31 // we want to initialize the struct in-place, otherwise we would get a stackoverflow 32 let buf: Box<BigStruct> = Box::init(init!(BigStruct { 33 buf <- init_zeroed(), 34 a: 7, 35 b: 186, 36 c: 7789, 37 d: 34, 38 managed_buf <- ManagedBuf::new(), 39 })) 40 .unwrap(); 41 println!("{}", core::mem::size_of_val(&*buf)); 42 } 43 } 44