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Comment by arinlen | Hacker News Reader

> If we assume that nullptr and auto mean the same as in C++ then what problem does nullptr fix in C?

For starters, it fixes the same problems it fixed on C++. I'm talking about stuff like automatic type conversion to ints and consequently being forced to babysit when your compiler called foo(int) instead of food(bar *) just because you passed NULL.

Also, keep in mind that these features are low-hanging fruits to any compiler writer, especially those who already maintain compilers that support C and C++. Thus the argument you should be making is not "why should C have these features" but "why should C be deprived from these features".

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> when your compiler called foo(int) instead of food(bar *) just because you passed NULL

That's what I meant that we don't have to worry about in C since you can't even have two different functions with the same name (assuming you meant foo instead of food).

> Thus the argument you should be making is not "why should C have these features" but "why should C be deprived from these features".

That's not an argument; that's a question. I wanted to know whether there was any reason to start using nullptr, like if there is a risk of making a bug if I use NULL. I did later find a page about nullptr in C [1] that talks about some risks of using NULL with varargs.

[1] https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3039.htm

> That's what I meant that we don't have to worry about in C since you can't even have two different functions with the same name

But you can have a macro foo which expands to a generic selection: <https://docs.microsoft.com/en-us/cpp/c-language/generic-sele...>

The committee should have standardized on defining NULL as (void*)0 which would have allowed _Generic to catch NULL with a void* type. This seems better than adding a whole new nullptr concept just for this one off "problem".

Great idea ! Now, try to convince the 30 implementers that did the wrong choice and will tell you they'll never change it because of backwards compatibility.

As addendum to that, in C++ there was a period before nullptr came to be, that best practice for null pointers was to use 0 directly instead of NULL exactly because of that.

https://stackoverflow.com/questions/54098794/is-null-guarant...

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