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+---- Thread: Rationale for 11.9 -- NULL constant (/showthread.php?tid=981)
Rationale for 11.9 -- NULL constant - stephen.parker - 09-09-2013
Can anyone explain what the rationale is for this rule? I could think of several arguments for why you shouldn't use NULL, and should prefer a plain 0 (as is generally preferred in C++). This feels like a stylistic issue.
Thanks,
stephen
Re: Rationale for 11.9 -- NULL constant - misra-c - 12-09-2013
The standard (ISO 9899:1999 6.3.2.3) defines a null pointer constant:
Quote:An integral constant expression with the value 0 , or such an expression cast to type void *, is called a null pointer constant.This means, for example that it is legitimate in the C language to compare a pointer expression with any form of integer constant expression including for example '\0' or any enum constant of value 0. For this reason it is advisable to use NULL wherever a null pointer constant is intended.
The semantics are subtly different in C++