Comment by nvlled

> Right, it's exactly like C, and we kinda all know how that worked out in practice already...

Production operating systems have been written in C, along the with the countless tooling, libraries and game engines (which you said are a poor fit for manual memory management) that modern systems depend on. I say it worked out it pretty well.

And zig did learn from the hard lessons from the industry and fixes a lot of problems with C. It also has a lot of affordances that makes it more than suitable for general purpose use.

> Arenas are not good for that because the arena as a whole has to outlive all of those poorly defined scopes & lifetimes, which is hard to do.

I don't what else to tell you, arenas outliving temporary allocations is exactly what it is made for, they go poof as soon as the arena owner is done. That's not hard, it makes it easier if anything. To give concrete examples, arenas are used on HTTP requests that are clean up in one go as soon as the request is done. They are also used on (possibly deep) recursive functions that are cleaned up as soon as the root function returns. Of course, you don't store arena-allocated memory elsewhere that outlives the arena, that would be dumb.

That's why you have to be consciously aware of the ownership and lifetimes that a piece of memory has. Ownership and lifetimes are just one part of the API contract of a function or module. You break it, that's on you. Having a compiler help with ownership model would be nice, but it's a not substitute for having a good mental model of your programs. It's not that different from the tradeoff of a having a less strict type system. Not every sanity check can or has to be performed at compile time. Zig also has debug allocators that catches a lot of memory mismanagement during testing. Hard to debug double-frees, use-after-frees and other things are a symptom of poor cavalier YOLO programming.

That all said, I do agree that manual memory management is really hard to do if you are used to just sweeping gigabytes of memory under rug, hoping the GC vacuum cleaner slurps it afterwards. It takes a mindset and a set of practice. But once you internalized it, it becomes second nature.

(Not to sound like a zig fanboy, I do think it's still rough around the edge and there are a lot of things I don't like. But manual memory management is not that big of a problem).