0561			[C] Right operand of assignment is not of compatible 'struct'/'union' type.
	Constraint violations				REFERENCE - ISO:C90-6.3.16.1 Simple Assignment - Constraints

/*PRQA S 750,759,1031,2213,2216,3132,3198,3199,3203,3210,3205,3408,3447,3604,3617,3623,3625 ++ */
extern void foo(int p);

struct ST1 { int si; char sbuf[10];};
struct ST2 { int si; char sbuf[10];};
union  UN1 { int ui; int uj;};
union  UN2 { int ui; int uj;};

extern struct ST1 st1a;
extern struct ST2 st2a;
extern union  UN1 un1a;
extern union  UN2 un2a;

extern int var;
extern int *pi;
extern char cbuf[10];

extern void test(void)
{
    struct ST1 st1;
    union  UN1 un1;

    st1 = st1a;                        /*      */
    st1 = st2a;                        /* 0561 */
    st1 = un1a;                        /* 0561 */
    st1 = var;                         /* 0561 */
    st1 = pi;                          /* 0561 */
    st1 = cbuf;                        /* 0561 */

    un1 = un1a;                        /*      */
    un1 = un2a;                        /* 0561 */
    un1 = st1a;                        /* 0561 */
    un1 = var;                         /* 0561 */
    un1 = pi;                          /* 0561 */
    un1 = cbuf;                        /* 0561 */
}

See also:

• 0430 [C] Function argument is not of compatible 'struct'/'union' type.
• 0675 [C] Initializer is not of compatible 'struct'/'union' type.
• 0756 [C] 'return' expression is not of compatible 'struct'/'union' type.