makepad/libs/relax/compiler/tests/layout/layout_diff.rs

// Layout differential test: size_of / align_of / offset_of of ~100 types must equal rustc's
// (rustc_abi univariant field reordering, niches, enum niche filling and tag sizing).
// Run: tests/layout/run.sh <makepad binary> -- prints DIFF lines, or "layout_diff: N lines equal".
#![allow(dead_code)]
use std::cell::{Cell, RefCell, UnsafeCell};
use std::mem::{align_of, offset_of, size_of};
use std::num::{NonZeroU16, NonZeroU32, NonZeroU64, NonZeroU8};
use std::ptr::NonNull;

macro_rules! sz {
    ($($t:ty),* $(,)?) => {
        $( println!("{} size {} align {}", stringify!($t), size_of::<$t>(), align_of::<$t>()); )*
    };
}

macro_rules! offs {
    ($t:ty: $($f:tt),*) => {
        println!("{} size {} align {} offsets {:?}", stringify!($t), size_of::<$t>(), align_of::<$t>(), [$(offset_of!($t, $f)),*]);
    };
}

struct S1(u8, u32, u8);
struct S2 { a: u8, b: u64, c: u16, d: u8 }
struct S3 { a: bool, b: [u8; 16] }
struct S4(u8, [u8; 16]);
struct S5 { a: u32, b: (bool, u8), c: u16 }
struct S6((u8, u8, u8, bool), (u8, bool, u8));
struct S7 { x: char, y: u8 }
struct S8 { r: &'static u8, n: u8 }
struct S9 { a: u16, b: u8, c: u32, d: u8, e: u64 }
struct S10 { a: [u16; 3], b: u8 }
struct S11<T: ?Sized> { a: u8, b: u32, t: T }
struct S12 { a: u8, b: Option<bool>, c: u32 }
struct S13 { a: (), b: u8, c: [u32; 0], d: u16 }
#[repr(C)]
struct C1(u8, u32, u8);
#[repr(C)]
struct C2 { a: u8, b: u64, c: u16 }
#[repr(packed)]
struct P1(u8, u32, u16);
#[repr(packed(2))]
struct P2 { a: u8, b: u64, c: u8 }
#[repr(align(16))]
struct A1(u8, u16);
#[repr(transparent)]
struct T1(u32);
struct Nz(NonZeroU32, u8);
struct Fp(fn(), u8);
struct Bx(Box<u8>, bool);

#[derive(Clone, Copy)]
enum E1 { A, B, C }
enum E2 { A = -1, B = 0, C = 1 }
enum E3 { A = 300, B }
enum E4 { A(u32), B(u8), C }
enum E5 { A(bool), B }
enum E6 { A(bool), B, C, D }
enum E7 { A(char), B, C }
enum E8 { A(u64, bool), B(u8) }
enum E9 { A(u8, bool), B(u32) }
enum E10 { A(&'static u8), B(u8) }
enum E11 { A(E1), B }
enum E12 { A(u32, E1), B(u16) }
enum E13 { A { x: u8, y: u64 }, B { z: u16 } }
enum E14 { Only(u32, u8) }
enum E15 { Only(u8), Never(std::convert::Infallible) }
enum E16 { A(Option<bool>), B(bool), C }
enum E17 { A([u8; 3], bool), B(u16) }
enum E18 { A(u8), B(u8), C(u8), D(u8) }
enum E19 { A(NonNull<u8>), B, C }
enum E20 { A(Box<u32>), B(u32) }
#[repr(u8)]
enum R1 { A(u32), B }
#[repr(C)]
enum R2 { A(u8), B(u64) }
#[repr(C)]
enum R3 { A, B }
#[repr(i16)]
enum R4 { A = -5, B = 9 }
#[repr(align(8))]
enum R5 { A, B }
enum E21 { A(u16, u8), B(u8, u8, u8) }
enum E22 { A(u32, bool), B(u32), C }
enum E23 { A((bool, bool)), B }
enum E24 { A(Option<char>), B, C }

fn main() {
    sz!(bool, char, u8, u16, u32, u64, u128, i128, usize, f32, f64, (), &u8, &[u8], &str, &dyn Fn(), fn(), *const u8, Box<u8>, Box<[u8]>);
    sz!(Option<bool>, Option<char>, Option<u8>, Option<u32>, Option<u64>, Option<&u8>, Option<&[u8]>, Option<fn()>, Option<Box<u8>>, Option<NonNull<u8>>);
    sz!(Option<NonZeroU8>, Option<NonZeroU16>, Option<NonZeroU32>, Option<NonZeroU64>, Option<Option<bool>>, Option<Option<Option<bool>>>, Option<(u8, bool)>, Option<(bool, u32)>, Option<[bool; 3]>, Option<()>);
    sz!(Option<Option<char>>, Option<Option<&u8>>, Option<E1>, Option<Option<E1>>, Option<E2>, Option<E3>, Option<std::cmp::Ordering>, Result<u32, ()>, Result<bool, ()>, Result<&u8, u8>);
    sz!(Result<u8, bool>, Result<u32, u32>, Result<(), Box<u8>>, Result<u64, std::convert::Infallible>, Cell<bool>, Option<Cell<bool>>, UnsafeCell<bool>, Option<UnsafeCell<bool>>, RefCell<u8>, Option<RefCell<u8>>);
    sz!((u8, u32, u8), (u8, u16), (u32, u8, u16, u8), (bool, u64), ((u8, bool), u32), [u8; 0], [bool; 4], [(u8, u16); 2], (u8, [u32; 0]), (char, u8));
    sz!(E1, E2, E3, E4, E5, E6, E7, E8, E9, E10, E11, E12, E13, E14, E15, E16, E17, E18, E19, E20, E21, E22, E23, E24);
    sz!(R1, R2, R3, R4, R5, Option<R1>, Option<R3>, Option<E5>, Option<E6>, Option<E9>, Option<E14>, Option<E15>, Option<E17>);
    sz!(S1, S2, S3, S4, S5, S6, S7, S8, S9, S10, S12, S13, C1, C2, P1, P2, A1, T1, Nz, Fp, Bx);
    sz!(Option<S1>, Option<S3>, Option<S7>, Option<S8>, Option<Nz>, Option<Fp>, Option<Bx>, Option<T1>, Option<P1>, Option<S11<u8>>);
    offs!(S1: 0, 1, 2);
    offs!(S2: a, b, c, d);
    offs!(S3: a, b);
    offs!(S4: 0, 1);
    offs!(S5: a, b, c);
    offs!(S6: 0, 1);
    offs!(S7: x, y);
    offs!(S8: r, n);
    offs!(S9: a, b, c, d, e);
    offs!(S10: a, b);
    offs!(S11<u64>: a, b, t);
    offs!(S11<u8>: a, b, t);
    offs!(S11<[u8; 3]>: a, b, t);
    offs!(S12: a, b, c);
    offs!(S13: a, b, c, d);
    offs!(C1: 0, 1, 2);
    offs!(C2: a, b, c);
    offs!(P1: 0, 1, 2);
    offs!(P2: a, b, c);
    offs!(A1: 0, 1);
    offs!(Nz: 0, 1);
    offs!(Fp: 0, 1);
    offs!(Bx: 0, 1);
    offs!((u8, u32, u8): 0, 1, 2);
    offs!((u32, u8, u16, u8): 0, 1, 2, 3);
    offs!((bool, u64): 0, 1);
}