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flohofwoe | on: C++: The Documentary
> Usually poorly.

On the contrary. You can focus exactly on the features the higher level game code needs. The C++ stdlib is (for the most part) poorly designed, usually poorly implemented, the main reason for slow build times, and its complexity explodes because it needs to consider all edge cases that most code bases don't ever trigger.

A specialized dynamic array class in a few hundred lines (at most!) and with just the required features is much more useful than the 20kloc monster that's pulled in with `#include <vector>` and which doesn't even do bounds checking in the 'idiomatic' usage.

Chaosvex | parent | next
Saying it doesn't even do bounds checking (in release builds) is to miss one of the major points of C++ - not paying for what you don't need. It's not a mistake, it's a feature.

You complain about it not being suitable for game development in one comment but then expect bounds checking in release builds? You're sitting in multiple lanes at the same time.

NIH implementations are usually grossly inferior because as it turns out, it's quite hard to get it right and those edge-cases aren't important until you start getting bitten by them when you'd rather be shipping features.

flohofwoe | root | parent | next
> bounds checking in release builds

Bounds checking overhead is negligible for all but the absolutely hottest code paths (fwiw we shipped active asserts, including bounds checking asserts in all the PC games I was involved with - carefully monitoring the overhead of course).

The main reason to not use the stdlib isn't so much about squeezing out the last bit of performance, but about control of what actually happens under the hood (and also compilation times). The overall runtime cost of all those active asserts (not just the range checks, everything) was somewhere in the 2..3% range, which is fine when budgeted for upfront.

Chaosvex | root | parent
That's your opinion, others won't agree and would much rather not pay the price at all.
imtringued | root | parent
Those asserts probably saved a lot of development costs and increased the robustness of the software, which is worth a lot more than a few percent on a benchmark.

I personally am more conservative on those things. I'll pick the fastest thing that is reliable.

bluGill | root | parent
Are we talking about games or medical devices here? I expect different things from them. If a medical device needs to turn off bounds checking to get results I'm concerned enough to not want to let anyone use it. If a game can get a slight performance improvement I'm all for it, who cares if it crashes, it is just a game.
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samiv | parent | next
Yes I don't disagree that sometimes a specific container or a data structure is great for the problem. Problem is that most of the game code and related code (so tooling,editor, auxiliary engine code) does need a typical STL type functionality and then when the org has "omg no STL" blanket rule someone ends up implementing STL and that's almost always worse than the STL that ships with the tool chain. Even worse..it'll be missing features and data structures and then people have to write sub-optimal code to work around it's limitations.
bluGill | root | parent
Top tier game orgs are often large enough to have good people write their own library with the correct compromises. They also tend to need micro performance improvements enough to be worth it.

Most of the rest of us STL is good enough.

tarnith | root | parent
Yeah, EA open sourced their STL, although now that C++23 is supported (aside from on MSVC? Still not flat_map there?!?) there is some replication in the STL.

Not uncommon for audio companies to also write their own containers and internal STL for ex. plugins as well.

demorro | parent | next
I find it hard to agree that the stdlib is poorly designed and implemented. In my entire career it has pretty much worked entirely to spec.

Yes, it can exhibit non-optimal performance, and in some specific cases (regex's especially), extremely poor performance, but that's not the same as being poorly designed and implemented, especially given the breadth of the thing.

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pjmlp | parent
Which is why one of the security measures in C++26 is to make bounds checking idiomatic, finally.