Synopsis

(Required) The value of errno shall only be tested when the last function to be called was an errno-setting-function.

Enabled by default

Yes

Severity/Certainty

Medium/Medium

Full description

errno is tested after a call to function that is not an errno-setting-function.

Coding standards

Code examples

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

#include<mc3_types.h>

void f ( void )
{
    float64_t f64;
    errno = 0;
    f64 = atof ( "A.12" );
    if ( 0 == errno ) /* Non-compliant */
        {
            /* f64 may not have a valid value in here.
             */
        }
}

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

#include<mc3_types.h>

void f ( void )
{
    float64_t f64;
    errno = 0;
    f64 = strtod ( "A.12", NULL );
    if ( 0 == errno )    /* Compliant */
        {
            /* f64 will have a valid value in here. */
        }
}