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"C++ has a rather odd culture..."

I have been writing C++ professionally for 15 years and agree. It has excellent ecosystem in several domains. On the other hand, in some areas the user needs to deal with incomprehensible and user hostile tooling and ecosystem glitches.

The weird thing is that more often than not the latter pathologies are considered "just fine", which just baffles me. Modern setups like Rust and it's tooling has demonstrated clearly that high performance native language has no intrinsic requirements to be user hostile.

Some people like to think that dealing with C++'s unnecessary complexities is somehow virtuous, when in fact they are a a bug of the platform (but one you need to deal with since if you need to write C++, you really need to write C++).

> Compare this with Java, or python or whatever, where the culture and focus is very much about "can you solve a problem / implement a solution using this language <or not>?" rather than "of the dozens of different ways to do this... what are the differences between each one".

We cannot optimize much in Java or Python, so of course we do not focus on the different ways of doing the same thing. C++ is needed in cases where the differences matter, so of course we care about the differences.

I would phrase this slightly differently.

We can't push Java or Python to be maximally efficient (not wasting a single cycle or byte over the absolute optimum), so we don't use them for use cases where that would matter. Therefore, we don't try to push Java or Python optimisation as far as possible. Being faster is always nicer, but it can never be essential to be optimal, because you wouldn't be using those languages if it was.

Whereas we can push C++ that far, so we do use it for use cases where absolute optimality matters. Hence the community around it values the ability to do that, and we end up with all sorts of weird and awkward stuff.

C++ also has a lot of weird and awkward stuff that is nothing to do with this, i should add. Most of that is ultimately due its age and C heritage, i think.

Firstly, let's dismiss this idea that C++ can avoid wasting a single cycle or byte, it doesn't aim for that. It aims for a much lower bar, albeit still a significant achievement - it says you won't do better by hand. It will very occasionally not meet this lower bar because some people like perverse challenges. That ludicrously fast Fizz Buzz implementation (so fast that inter-core CPU bandwidth alters how fast it seems) in raw machine code can't be duplicated in C++ for example. But on real problems with real programmers you won't do better by hand and should stop trying.

OK, so there are limits. Further though the fact that you sometimes want to be able to do something did not require that C++ insist upon you doing that all the time.

There are places where they didn't. HN recently discussed structure layout and padding. You can write a C++ program with explicit structure layout and padding (I think this may not be portable though) which can significantly alter performance - but you don''t have to. If you're OK not worrying about it, C++ won't optimise layout for you (as Rust would) but it also won't ask you questions about alignment and layout, they're just left alone.

But for some things they insist. Manual memory management for example. The language doesn't (in practice) provide garbage collection, so you are responsible for picking up the trash even if you don't care about that problem. Arithmetic is another, even if it's not performance critical for you, C++ insists you need to cope with the vagaries of machine arithmetic anyway and care about things like overflow and Not-a-Number.

And this burden imposes a real cost on programmers which, at the end of the day, means they actually produce slower/ bigger code than they might have.

> Firstly, let's dismiss this idea that C++ can avoid wasting a single cycle or byte, it doesn't aim for that. It aims for a much lower bar, albeit still a significant achievement - it says you won't do better by hand.

You're referring to the "zero-overhead" goal of new C++ features. I think the above poster was talking more generally about one's ability when using a language to implement some critical subset as fast as possible or with as little memory use as possible. I suppose it's arguable if you're still doing C++ when you use intrinsics. Though I think pragmas are certainly fair game. At least C++ (and C considered as a subset) is the biggest high-level language with such a possibility.

Zero overhead abstraction is often discussed, but the explicit design goal of C++ according to its author is that there shouldn't be a language between C++ and ASM. I.e. while you can do better in asm, it shouldn't be possible to do better in another higher level language C++. If you can it means that C++ is missing some feature.

Most optimization techniques work just as well in Python as they do in C++ or Brainfuck.

> C++ has a rather odd culture... it's very a very fundamentalist/extremist one, all providing the optimal way to do things with no / little extra runtime overhead, but with no regard at all to compile times, readability, etc.

It think this is attributed to fundamental rule of not breaking legacy language features. That is the number one rule (much like how Linus is iron fisted about not breaking user space in the Linux environment). However, there is a lot of wiggle room in the way binaries are generated, so compiler authors can get really creative with their optimisation efforts.

> It think this is attributed to fundamental rule of not breaking legacy language features. That is the number one rule

No. The number one rule in C++ is "don't pay for what you don't use".

To be more specific it's "don't pay in runtime cost for what you don't use". As the OP says that courtesy isn't extended to compile times - simply enabling C++17/20 can balloon your compile times even if you don't touch a single new feature, because the standard headers get more and more bloated with each new version.

https://build-bench.com/b/FW3EPgB1t0fmpIr1TB_vJbbb0Vw

Which is exacerbated even more by the leaky #include system, where you can easily end up pulling enormous standard headers into translation units that don't even reference them directly. The only reprieve is to ban most of the standard library from your project and write your own leaner version from scratch, as most big C++ projects end up doing.

There are ways to speed up compilation. It can be done in parallel, and you can get a lot of cores into a developer desktop these days. Plus you can get unlimited amounts of distributed cores in the cloud. Compilation can also be sped up with pre-compiled headers, which will soon be replaced with C++20 modules which will help compilation improve in the future as compilers improve their support for modules. With incremental compilation, you do not need recompile the whole project after every change. Linking in large statically linked binaries is a big bottleneck, but incremental linking is possible in some cases. You can also break your project into multiple shared libraries (DLLs) , and link dynamically at run-time for debugging. It can then be re-built with static linking for a release build. Continuous Integration systems can also help hide the latency of compilation from developers by continuously running build and test processes in the background on a cluster.

ccache can considerably cut down compile times. Simple to install and minimal config, no change to tooling or workflow...

https://ccache.dev/

> There are ways to speed up compilation. It can be done in parallel, and you can get a lot of cores into a developer desktop these days.

I'd start with the very basics, such as using forward declarations, encapsulation, and the pimpl idiom to not drag unnecessary #includes into your translation units.

Also, the compilation bottleneck sometimes lies in IO, thus moving your build folder to a RAM drive can speed up things significantly with zero effort.

It's possible, and I know first hand it is. It requires quite a bit of work though.

It might be easier to just have quick compile times though!

Number two rule is staying similar to C and not breaking legacy features. That's the fundamental difference with Rust (although you can argue that when languages get bigger you are always bound to become a slave of the language)

I'd argue not breaking old code has precedence over zero cost abstraction.

It's not a contest. They're both fundamental requirements. Mom doesn't like one of them best.

But indeed, when the option is between maintaining backward compatibility or further reducing overhead, the C++ committee usually choses the former, at least on the library side. See for example the less then ideal unique_ptr constructor or the invalidation guarantees of the unordered containers.

> It think this is attributed to fundamental rule of not breaking legacy language features.

Is this really all that unique to C++? Or are you saying that it's just particularly painful for C++ due to where it started from?

It's not that unique to C++. It's a property of useful things that have been successful for a long time.

Not unique to C++, but strongly enforced. Work groups that standardise new C++ features is very reluctant to make any breaking changes.

Stick to non-modern c++ imo.

Also in java everything has to be under the constraints of an object before you can do the stuff you want to do. It does seem more extremist to me because it's literally encoded in the compiler ruleset.

> it's very a very fundamentalist/extremist one

This is C++'s moto and core feature.

Don't think it's for you? Then it's not for you.

> and focus on the arcane finer points of move semantics, rvalue references, ranges, concepts, all this new stuff...

This is new stuff to learn but once you do you realize it's super helpful.