cc17

Is there such a thing as nullptr (or equivalent) in modern C standards?

I included a check for nullptr in a line of C code. The compiler (gcc) complained when using -std=c17 as well as -std=gnu17.

Is there such a thing as nullptr (or equivalent) in modern C standards? (C11, C17)

If not, then why?

Solution

  • No, C still uses NULL for a null pointer.

    C++ needs a dedicated null pointer literal because it has overloading and template type deduction. These features get confused by NULL, which expands to 0 (or something like that) in C++. However, the risk of such confusion in C is small (maybe _Generic can get confused by this), and in addition, C can use (void*)0 for a null pointer, which mitigates this risk even more.