I was MIA for a couple months, so I'm very unsure whether I caught everything, but here is what happened since 9.0.0.
I think we don't traditionally highlight in release notes that something was a result of GSoC. I don't have an opinion here, just don't see much of it.
I think this one's out of alpha already (i.e., cplusplus.PlacementNew). I'd also bump it to the top because it applies to more users.
Not much here, mostly bugfixes.
Let's make this more concise: "Dead stores checker now warns about nested dead stores.". While it was originally unclear whether this should be on by default, i think there's relatively little motivation in disabling this option now that everybody liked it :)
Oh, wait, there was this D71728 thing.
(probably no need for a separate section for Objective-C)
I missed out on the transition to github, so I suspect that the commit access will only be extended to it after tagging rc2. I think it would be better if you committed this on my behalf, thanks! :)