rustType errorMedium

Unexpected behavior when converting structs in Rust

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What it should do

Convert a struct A to struct B. Example: convert_structs(a) -> b

What happens instead

Runtime error: attempted to transmute between types with different memory layouts

struct A { x: i32, y: i32 }
struct B { z: i64 }

fn convert_structs(a: A) -> B {
    unsafe { std::mem::transmute(a) }
}

fn main() {
    let a = A { x: 1, y: 2 };
    let b = convert_structs(a);
    println!("{}", b.z);
}

Test a custom input to verify an edge case (e.g. empty lists, negative numbers, duplicates).

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This bug belongs to the type errors pattern

Totals that concatenate, sorts that put 10 before 9, comparisons that refuse to run.

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struct A { x: i32, y: i32 } struct B { z: i64 } fn convert_structs(a: A) -> B { unsafe { std::mem::transmute(a) } } fn main() { let a = A { x: 1, y: 2 }; let b = convert_structs(a); println!("{}", b.z); }

Unexpected behavior when converting structs in Rust

What it should do

What happens instead

More type errors to practise

Unexpected behavior when converting structs in Rust

What it should do

What happens instead

More type errors to practise