<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><br class=""><div><br class=""><blockquote type="cite" class=""><div class="">On Sep 5, 2017, at 18:37, Nevin Brackett-Rozinsky via swift-dev <<a href="mailto:swift-dev@swift.org" class="">swift-dev@swift.org</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div dir="ltr" class=""><div class="gmail_extra"><div class="gmail_quote">On Tue, Sep 5, 2017 at 6:08 PM, Slava Pestov via swift-dev <span dir="ltr" class=""><<a href="mailto:swift-dev@swift.org" target="_blank" class="">swift-dev@swift.org</a>></span> wrote:<br class=""><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div style="word-wrap:break-word" class=""><div class=""><div class="">We expect that “define your struct in C” is still the way to go for layout compatibility with other languages and systems.</div></div></div></blockquote><div class=""><br class=""></div><div class="">Are there plans (however tentative) to eventually make it possible to specify the exact memory layout of a struct in Swift?</div><div class=""><br class=""></div><div class="">It seems like something we will have to tackle in order for Swift to become a serious systems-level programming language.</div></div></div></div></div></blockquote><br class=""></div><div>There's nothing inherently wrong with having a 'packedLayout' attribute or similar (as long as the compiler can enforce alignment requirements for non-trivial types), but neither is it urgent since you can do the same thing in C. It's a feature that can be added at any time, just not to <i class="">existing</i> fixed-contents structs.</div><div><br class=""></div><div>Jordan</div><br class=""></body></html>