Synopsis

Do not access a variable through a pointer of an incompatible type.

Enabled by default

Yes

Severity/Certainty

Medium/Low

Full description

Modifying a variable through a pointer of an incompatible type (other than unsigned char) can lead to unpredictable results. This check is identical to MISRAC2012-Rule-11.1.

Coding standards

Code examples

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

#include <stdlib.h>

void example(void) {
  int (*fptr)(int,int);
  (int*)fptr;
}

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

typedef void ( *fp16 ) ( int n );
typedef fp16 ( *pfp16 ) ( void );

void example(void) {
    pfp16 pfp1;
    ( void ) ( *pfp1 ( ) );   /* Compliant - exception 2 - cast function
                               * pointer into void */
}