Synopsis

(Required) The validity of values passed to library functions shall be checked (>0 case).

Enabled by default

Yes

Severity/Certainty

Medium/Medium

Full description

A parameter value (<=0) might cause a domain or range error. This check is identical to MISRAC2004-20.3_a.

Coding standards

Code examples

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

#include <math.h>

void gtz(double d1, double d2) {
  double e;
  e = tgamma(-1.0);   /* const not in range */
  e = tgamma(d1);     /* var not checked */
  if(d1 > 0) {
  } else {
    e = tgamma(d1);   /* checked but in wrong branch */
  }
  if(d1 > 0) {
    d1 = d2;
    e = tgamma(d1);   /* checked but updated */
  }
}

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

#include <math.h>

void example(double d) {
  double e;
  if(d > 0) {
    e = tgamma(d); /* checked before use */
  }
  if(0 < d) {
    e = tgamma(d); /* checked before use */
  }
  if(d <= 0) {
  } else {
    e = tgamma(d); /* checked before use */
  }
  if(0 >= d) {
  } else {
    e = tgamma(d); /* checked before use */
  }
  e = tgamma(1.0); /* constant > 0 */
}