[swift-evolution] [Proposal Draft] Flexible memberwise initialization

[Chris Lattner]

> On Dec 22, 2015, at 11:38 AM, Félix Cloutier <felixcca at yahoo.ca> wrote:
> 
> 
> Sorry to sidetrack the discussion, but does that mean that using `let` properties in a type where memory layout is important is possibly not forward-compatible?

Swift has no support for such a type, when it does, it should be opt in.