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meeting-notes/20181025.md

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+# Meeting 4: 25 Oct 2018
+
+It’s that time again! UNSAFE CODE UPDATE TIME! You can view the entire discussion [here](https://rust-lang.zulipchat.com/#narrow/stream/136281-wg-unsafe-code-guidelines/topic/meeting.202018-10-25). We’re transitioning to a new active discussion topic: **Validity Invariants**. Over the next two weeks, we’ll be wrapping up the current discussion (data representation) and starting to move on to new topics.
+
+## Summary
+
+Thank you to everyone who participated in the data representation discussions and a *huge* thank you to Niko and Ralf for their writeups on structs/tuples and unions (and ubsan for volunteering for function pointers). Here’s the section outline:
+
+- Introduction to data representation
+- Integers and Floating Points
+- Structs and Tuples
+- Unions
+- Enums — [HELP NEEDED](https://github.com/rust-rfcs/unsafe-code-guidelines/issues/10)
+- References and Pointers — [HELP NEEDED](https://github.com/rust-rfcs/unsafe-code-guidelines/issues/16)
+- Function Pointers
+
+While we're talking about writeups, I want to make a note about how to handle disagreement/bikeshedding/etc. With the work we're doing, I totally expect some of that to happen. Instead of getting too deep in the weeds/bikeshed, I'd prefer to document the discussion and different points (which @nikomatsakis did a great job in the structs/tuples writeup) so that we can continue to make progress and potentially revisit the issues at a later date.
+
+That said, we don’t want to leave dangling issues. Lingering points from previous discussions that might require a “circle back” at a later point should be noted with a FIXME/TODO/gh label.
+
+Unfortunately, neither Niko nor I will be at RustFest Rome, but if people are interested, you should organize a face-to-face! I will be organizing a face-to-face in Orlando, and hopefully at a Rust gathering next year.
+
+Daylight savings time is upon us—you can keep track of timezones via the calendar invite (ping @nikomatsakis). If you’d like to participate in meetings synchronously and the current time doesn’t work for you, bring it up [here](https://rust-lang.zulipchat.com/#narrow/stream/136281-wg-unsafe-code-guidelines/topic/meeting.20time.20and.20DST).
+
+We’re also [TWITTER OFFICIAL](https://twitter.com/rust_unsafe) 🦄
+
+## What's next?
+- Finish writeups for *data representation*
+- Start discussions for *validity invariants*
+