Synopsis

(Required) The expansion of macro parameters shall be enclosed in parentheses.

Enabled by default

Yes

Severity/Certainty

High/Medium

Full description

An expansion of macro parameters was found that is not enclosed in parentheses. This check is identical to MISRAC++2023-19.3.4.

Coding standards

Code examples

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

void example(void) {
  int r;

#define M( x, y ) ( x / y )

  r = M ( 1 + 2, 1 - 2 );
}

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

static struct str {
  int val;
} s;

void example(void) {
  int r;
  int a[10];

  /* already enclosed in macro def*/
#define M( x, y ) ( ( x ) << ( y ) )
  r = M( 1 + 2, 3 + 4 );

  /* no need after ## or # */
#define N( x ) a [ ##x ] = (x)
  N ( 0 + 2 );

  /* no need after . or ->, member name */
#define MEMBER( S, M ) ( S ).M
   r = MEMBER ( s, val );

  /* enclosed in inner macro */
#define F( X ) G( X )
#define G( Y ) ( Y )
   r = F ( 2 );

  /* enclosed at invocation site,
     even single literal should have parentheses */
#define M( x, y ) ( x / y )
   r = M ( ( 1 ), ( 2 + 3 ) );
}