Synopsis

(Required) Boolean operations whose results are invariant shall not be permitted.

Enabled by default

Yes

Severity/Certainty

Low/Medium

Full description

A comparison using ==, <, <=, >, or >= was found that always evaluates to false. This check is identical to RED-cmp-never.

Coding standards

Code examples

The following code example fails the check and will give a warning:

int example(void) {
  int x = 10;

  if (x < 10) {  //never true
    return 1;
  }

  return 0;
}

The following code example passes the check and will not give a warning about this issue:

int example(int x) {

  if (x < 10) {  //OK - may be true
    return 1;
  }

  return 0;
}