Using repr(isize/usize) for C-like enumerations with values that don’t fit into an i32 can lead to truncated variant
values on 32-bit architectures, potentially causing unexpected behavior.
Code examples
Noncompliant code example
#[repr(usize)]
enum NonPortable {
X = 0x1_0000_0000, // Noncompliant
Y = 0,
}
Compliant solution
#[repr(u64)]
enum Portable {
X = 0x1_0000_0000, // Compliant
Y = 0,
}
