fragment of code from the Clang documentation page

Question

In the Clang documentation page there is a fragment of following code:

struct seven_words {
  int c[7];
};

void test() {
  struct seven_words a, *p;
  p = &a;
  p[0] = a;
  p[1] = a;
  p[2] = a; // warn
}

Why the checker warns only at the line with accesing to p[2] whereas there is a segmentation fault on line p[1] = a;. Is it a limit of the checker or there is something that I don't understand?

Have you tried reproducing it? Most likely it is just a typo. — user7860670, Dec 12 '17 at 16:54
I’d say it’s either a bug in the checker (which is labelled as alpha) or in the documentation. As @VTT suggests, the documentation is more likely. — Daniel H, Dec 12 '17 at 17:09
Either way, it would be more productive to post on their bug tracker than on SO. — underscore_d, Dec 12 '17 at 17:10
Yes, I've tried to reproduce it.The checker doesn't produce any warning even about line p[2] = a; — Wojciech Marzec, Dec 12 '17 at 17:40

score 2 · Answer 1 · answered Dec 12 '17 at 17:51

2

The documentation is incorrect. (Or, if it correctly documents the behavior of the analyzer, the analyzer is deficient because it fails to detect a clear problem.)

answered Dec 12 '17 at 17:51

Eric Postpischil

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fragment of code from the Clang documentation page

1 Answers1