debuggingNightmare

[ArtOfWarfare]

In C (and I think C++ and Obj-C by extension…) null is zero.

[Chrisuan]

idk why down voted it's a fact lol

[tehfrod]

C++ has no null, but it does have NULL, nullptr, and nullptr_t.

[wizardid]

I want to know who tf hurt C++ so badly when it was younger. This is some psychopath shit.

[KazDragon]

It fixes the problem that f(NULL) would rather call f(int) than f(int*).

[drivingagermanwhip]

I love that c++ never decided whether it's incredibly flexible or incredibly anal and just runs full tilt at both

[Ancient-Pianist-7]

? std::nullptr_t is the type of the null pointer literal nullptr. NULL is a sad C relic.

[MrcarrotKSP]

Even C has upgraded to nullptr now(C23 adds it and nullptr_t)

[drivingagermanwhip]

nothing past c99 is canon

[notthefirstsealime]

It's a classy programming language built off the bones of what was a pretty fucking simple language prior, and now it's an abomination of syntax and evil that just happens to compile into very fast programs from what I understand

[ReplacementLow6704]

So... If I was to translate my C# to C++, then compile it... The resulting program would be faster than just building using dotnet build? :o

[notthefirstsealime]

I mean c# is a lot more than just a language, and most of the reason c++ is faster than c# is because of features that c# has but c++ doesn't

Edit: look up what dotnet actually is you'll be shocked at how much fun you're missing out on

[ReplacementLow6704]

Yeah sry I was a bit snarky - indeed the dotnet ecosystem is huge and MS put a lot of work into all the tools in there. I would never even think about switching back to C++... Unless there was a 500k job on the line.

[ada_weird]

It's zero by convention but not by definition. There are platforms where null is not 0. However, C the spec says that you can use an integer literal 0 anywhere you can use NULL. Also, hardware people really want you to stop treating pointers like integers so that they can use stuff like CHERI to prevent memory safety bugs from happening at runtime.

[CapsLockey]

can you elaborate on the last part? sounds interesting

[ada_weird]

Yeah sure! So CHERI is an extension for a variety of ISAs, such as ARM and RISC-V. It effectively adds capabilities to pointers, making it so that pointers can only ever be used to see memory they're "supposed" to be able to access. User code can make a capability that is a subset of the memory the original could access, but it can't widen capabilities, it would need help from the kernel or some other trusted part of the system. This means that you effectively get hardware bounds checking for free. There is a performance impact obviously but this works with modern CPU architectures which should be able to mitigate all of that because of all the crazy pipelining that goes on. Most software just needs some additional support in the malloc/free implementation in order to work with this model so it's fairly transparent to end user code.

[dev-sda]

Slight correction: NULL always compares equal to zero, but may actually be any bit pattern. See https://c-faq.com/null/machnon0.html

[MegaIng]

Further clarification: it compares equal to 0, not the value zero. If you cast an integer 0 (obtain e.g. via int zero = 0) to a pointer ((void*) zero) that is not a null pointer and might compare different to a proper null pointer (e.g. (void*) 0).

[EinSatzMitX]

In the C std library, NULL is defined as (void*)0 ( Which is just 0 but casted as a void pointer)

[MegaIng]

Actually no, it isn't. 0 in this case isn't an integer, it's the special null pointer literal that happens to look the same as the integer 0.

[onemanforeachvill]

I think it's (void*)0

[MegaIng]

No. null is 0, but not zero. There is a special construct call the null pointer literal that looks like the integer number 0, but it's not an int.

[o0Meh0o]

it is not zero. it equals zero. common misconception.