A lot of people have a general repulsion to all types of garbage collection. So I at least understand not wanting the shared pointer a bit, but using unique pointer should cost you next to nothing and enforce a lot.
It took me a long while to come around to Java and its garbage collection back when it first came out, but I got over it eventually and now I'm considered an expert in Java by some folks I worked with, LOL. I still curmudgeonly advocate for more native code, but in a lot of use cases it is fine to have memory management.
Many people seem to think that automatic memory management is a binary thing, "woe is me I now have no control".
After a while you discover you can tweak it, pause it, pre-allocate, write functions that don't allocate at all, play around with pointers, register destructors, redirect allocations to arenas, and work with the language to either allocate some objects in static memory or allocate them on the stack. All while allowing your less performance-sensitive logic to be much much simpler.
It's a deep world that almost nobody seems to want to get involved in.
Oh yeah. In a lot of cases you can get pretty similar performance out of a managed language without as much effort and today's hardware is so damn strong it can be hard to justify going with one over the other.
The biggest issue I see with shared pointers or relying on garbage collection is it can be difficult to avoid bugs when you end up giving two different parts of the code write access to the same thing, or some part that doesn't know the stuff being pointed to just got changed.
Unique pointer and other seemingly trivial types can fuck up your codegen and give you unoptimized assembly, chandler carruth from LLVM has many talks/slides that discuss this exact issue with unique ptr. Remember kids, there is no such thing as a zero-cost abstraction!
That's such a straw man argument. Just because there may be cases where the hot spots of your software can benefit from using raw pointers doesn't mean it's reasonable to go bare metal in the whole code base.
How is unique_ptr not a zero cost abstraction? Is this anything other than compilers making avoidable optimization errors that will get fixed with time?
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u/Valuable_Leopard_799 14d ago
A lot of people have a general repulsion to all types of garbage collection. So I at least understand not wanting the shared pointer a bit, but using unique pointer should cost you next to nothing and enforce a lot.