I meant to write about CppOnSea for a while. The event is already a month in the past. So I better write down my impressions as long as I can remember anything. My comments will probably be shorter than had I written it down earlier.
Last year I learned from a podcast about a new C++ conference in Great Britain. It made a good first impression. As the details trickled in over the course of the ensuing months, I started to think it would be worth visiting.
When I asked around in the office who would join, I got only one positive answer. Reaching the venue by plane would not only be impractical, but I also didn't really want to pollute the atmosphere. So I proposed to drive there with my electric car.
I checked the weather in advance, since what I wanted the least, was driving through a snow storm for a whole day. Exactly the night before we left, we had a good portion of fresh snow. As it was even on the highway, we made rather slow progress in the first two hours. The rest of the trip was uneventful, with the exception of having to drive over a small pass because a tunnel was closed in the Elsass. We took the tunnel below the channel. It is different than riding through the Swiss mountains on the back of a train, but not too much different. We arrived late in the evening at a nice old hotel on the cliff right next to the event hall where the conference was going to be. The breakfast was a lot better than what I remembered from previous stays in the UK.
A baroque event hall built right into the cliff served as the venue for the conference. During the breaks we had a nice view onto the sea, and sometimes we had the impression we could see France on the other side.
The opening keynote was funny and entertaining. That is all I remember.
The speaker presented his library for immutable data structures. They enable a more functional style. It sure has something to it, but I don't see a use case in anything that I am currently involved.
He had a much broader scope than what I considered so far. It is interesting to know, but I don't think I will use any of it in the foreseeable future. But it triggered me to think about using emscripten again.
I have known and sporadically used clang on linux for some years. But even though it is a great compiler I didn't use it too much because you would have to compile everything yourself, rather than using dependencies from the apt repository. Also I knew that clang is shipped with VisualStudio, but only for cross compiling to ARM. What was new to me, is that you can also compile (but not link) regular desktop applications on Windows, with some work even MFC applications. This in turn allows the usage of clang tidy, which a good portion of this talk was about. What was also new to me, is that the MSVC compiler switch /permissive-
causes VisualStudio to use a completely new compiler that is no longer built with YACC, but is much more standards compliant. This better compiler introduces breaking changes to old code. That is why we didn't use the flag so far. But I think it would be good to slowly introduce it module by module. This way we could sanitize the codebase, and maybe later start using the clang tools.
This one was in the main hall, and for all attendees. It had nothing to do with C++ or with programming per se. It was more about social interactions with minorities. I still don't know why there was such an emphasis on this topic. But it seems to be a phenomenon at lots of IT conferences lately.
Building the CAD I am working on can take up to an hour if I build only locally. Over the years we optimize the pre compiled headers from time to time, but also the linker takes a lot of time. So this was especially interesting for me.
The speaker ran through an extensive list of approaches to reduce build times. Lots of it was not applicable for us, or too esoteric. But one main takeaway was that I should look into union builds. He mentioned cotire to help with that. When we switched to cmake a couple of years ago, I tried to use cotire to simplify the handling of pre compiled headers, but couldn't really get it to work. Maybe it is time to re-visit it.
This one was entertaining, but I didn't learn much from it, except for the British humor.
In a way it is surprising that C++ has no linear algebra library standardized by now. Because of this many independent libraries exist, and many companies wrote their own implementations. This could lead to the conclusion that it comes too late. But I was delighted to learn, that the proposed library mixes well with existing libraries and data structures. So we will see how much of it we end up using when it is finally released.
This one was about tooling. Nothing that I think will be applicable for us.
This one was informative and entertaining. He had many good examples of how amazingly good modern compilers are at optimizing our code, and work around bugs in certain CPUs. This video is worth watching even if you don't work with C++.