The C++ standard for the F-35 Fighter Jet [video]

Did they really have to tell their programmers this ? (see Page 52) AV Rule 174 (MISRA Rule 107) The null pointer shall not be de-referenced.

There are old idioms in C where null pointers are intentionally dereferenced to induce the expected outcome. Not the best way to write that code because beyond being less explicit about intent it also isn't guaranteed to work.

The rule is likely speaking to this code.

Commercial jet airliners, which in all likelihood you have flown with, have system controllers which intentionally dereference the null pointer. Yes, I have seen the code, the intention was an integrity check at startup, which computed a checksum of the memory, which included the value stored at address zero.

The rule isnt there to say "don't do this". It's there to say "you must prove that this holds true, in any circumstance".

I've done it, I think more than once.

I was getting to a point in the code. I could tell by a log statement or some such. But I didn't know in what circumstances I was getting there - what path through the code. So I put in something like

  char *p = 0;
  *p = 1;

in order to cause a core dump. That core dump gave me the stack trace, which let me see how I got there.

But I never checked that in. If I did, I would expect a severe verbal beating at the code review. Even more, it never made it into release.