Synopsis

(Required) Identifiers declared in the same scope and name space shall be distinct.

Enabled by default

Yes

Severity/Certainty

Low/Medium

Full description

Identifier names were found that are not distinct in their first 63 characters from other names in the same scope.

Coding standards

Code examples

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

/*         0        1         2         3         4         5         6     */
/*         123456789012345678901234567890123456789012345678901234567890123* */
extern int n01_var_hides_var____________________________________________63x;
static int n01_var_hides_var____________________________________________63y;

/*         0        1         2         3         4         5         6     */
/*         123456789012345678901234567890123456789012345678901234567890123* */
static int n02_function_hides_var_______________________________________63x;
void       n02_function_hides_var_______________________________________63y (void) {}

void foo(void) {
  int i;
  switch(f1()) {
  case 1: {
      do {
	for(i = 0; i < 10; i++) {
	  if(f3()) {
/*              0        1         2         3         4         5         6     */
/*              123456789012345678901234567890123456789012345678901234567890123* */
	    int n03_var_hides_var____________________________________________63x;
	    int n03_var_hides_var____________________________________________63y;
	  }
	}
      } while(f2());
    }
  }
}

/*   0        1         2         3         4         5         6     */
/*   123456789012345678901234567890123456789012345678901234567890123* */
enum E {
     n04_var_hides_enum_const_____________________________________63x
};

/*   0        1         2         3         4         5         6     */
/*   123456789012345678901234567890123456789012345678901234567890123* */
int  n04_var_hides_enum_const_____________________________________63y;

/*           0        1         2         3         4         5         6     */
/*           123456789012345678901234567890123456789012345678901234567890123* */
void bar(int n05_var_hides_parameter______________________________________63x) {
  int        n05_var_hides_parameter______________________________________63y;
}

/*      0        1         2         3         4         5         6     */
/*      123456789012345678901234567890123456789012345678901234567890123* */
#define n06_var_hides_macro_name_____________________________________63x 123
int     n06_var_hides_macro_name_____________________________________63y;

/*          0        1         2         3         4         5         6     */
/*          123456789012345678901234567890123456789012345678901234567890123* */
int         n07_type_hides_var___________________________________________63x;
typedef int n07_type_hides_var___________________________________________63y;


/*    0        1         2         3         4         5         6     */
/*    123456789012345678901234567890123456789012345678901234567890123* */
union U {
  int n08_field_hides_field________________________________________63x;
  int n08_field_hides_field________________________________________63y;
};

struct S {
  int n09_field_hides_field________________________________________63x;
  int n09_field_hides_field________________________________________63y;
};

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

/*           0        1         2         3         4         5         6             */
/*           123456789012345678901234567890123456789012345678901234567890123********* */
extern int   n01_var_in_different_scope___________________________________63x;
void         n02_different_function_name__________________________________63x (void) {
  static int n01_var_in_different_scope___________________________________63y;

  switch(fn()) {
  case 1:
    {
      int    n01_var_in_different_scope___________________________________63a;
    }
    break;
  case 2:
    {
      int    n01_var_in_different_scope___________________________________63b;
    }
    break;
  }
  {
      int    n01_var_in_different_scope___________________________________63c;
  }
  {
      int    n01_var_in_different_scope___________________________________63d;
  }
}

/*         0        1         2         3         4         5         6     */
/*         123456789012345678901234567890123456789012345678901234567890123* */
void       n12_var_hides_function_different_scope_______________________63x (void) {
static int n12_var_hides_function_different_scope_______________________63y;
}

/* exception for typedef of tag name*/
typedef struct s1 {
  int sf1;
} s1;

typedef union u1 {
  int uf1;
  int uf2;
} u1;

typedef enum e1 {
  ec1, ec2
} e1;

/* identifiers in different name spaces */
void foo(void) {
  int i;
  switch(f1()) {
  case 1: {
      do {
	for(i = 0; i < 10; i++) {
	  if(f3()) {
/*                 0        1         2         3         4         5         6     */
/*                 123456789012345678901234567890123456789012345678901234567890123* */
	    struct n03_var_hides_struct_tag_____________________________________63x {
	      int f1;
	    }      n03_var_hides_struct_tag_____________________________________63y;
	  }
	}
      } while(f2());
    }
  }
}

/*    0        1         2         3         4         5         6     */
/*    123456789012345678901234567890123456789012345678901234567890123* */
union n04_var_hides_union_tag______________________________________63x {
  int v1;
  unsigned int v2;
}     n04_var_hides_union_tag______________________________________63y;

/*   0        1         2         3         4         5         6     */
/*   123456789012345678901234567890123456789012345678901234567890123* */
enum n05_var_hides_enum_tag_______________________________________63x {
     n07_tag_hides_enum_const_____________________________________63x
};

/*   0        1         2         3         4         5         6     */
/*   123456789012345678901234567890123456789012345678901234567890123* */
int  n05_var_hides_enum_tag_______________________________________63y;

struct 
     n07_tag_hides_enum_const_____________________________________63y {
  int sf2;
};

void bar(void) {
/*    0        1         2         3         4         5         6     */
/*    123456789012345678901234567890123456789012345678901234567890123* */
  int n09_label_hides_var__________________________________________63x;
  {
/*0        1         2         3         4         5         6     */
/*123456789012345678901234567890123456789012345678901234567890123* */
  n09_label_hides_var__________________________________________63y:
    n09_label_hides_var__________________________________________63x = 1;
  }
}