NoUniqueAddress

Permits a field to overlap another subobject when target layout allows.

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Module std.layout

import std.layout;

Public declaration contracts and authored examples. A page can document several related symbols. Implementation bodies are excluded.

NoUniqueAddress

pub attribute NoUniqueAddress

Permits a field to overlap another subobject when target layout allows.

The attribute grants layout freedom but does not require overlap and does not weaken field lifetime, aliasing, or address-validity rules.

Example

module example.no_unique_address;
import std.layout as layout;
struct EmptyTag { }
pub struct TaggedCounter {
    [layout.NoUniqueAddress]
    priv Tag: EmptyTag;
    pub Value: i32;
}
fn Main() -> i32 { return 0; }

Documentation snapshot: October 24, 2026 About versions ↗