[PATCH] D72705: [clang][checkers] Added new checker 'alpha.unix.ErrorReturn'.

[Balogh, Ádám via Phabricator via cfe-commits]

baloghadamsoftware added a comment.

Please consider the following test cases:

  void test_NullCorrectCheck3() {
    void *P = aligned_alloc(4, 8);
    use(*P); // A developer inserted this line before the check by mistake. This will be a null pointer dereference.
    if (P == NULL) {
    }
  }

Or:

  void test_NullCorrectCheck3() {
    void *P = aligned_alloc(4, 8);
    if (dice()) { // A deloper introduced a new branch, but by mistake, before the check.
      if (P == NULL) {
        use(*P);
      }
    } else {
     use(*P); // No check in this branch, thus a null pointer dereference.
    }
  }

False positive (or not?):

  void g(void*); // Unknown function
  
  void test_NullBadCheck1() {
    void *P = aligned_alloc(4, 8);
    g(P); // If g() checks its parameter for null, then false positive. If not, then true positive.
  }


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D72705/new/

https://reviews.llvm.org/D72705