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      1 /*	$NetBSD: msg_115.c,v 1.11 2023/03/28 14:44:34 rillig Exp $	*/
      2 # 3 "msg_115.c"
      3 
      4 // Test for message: %soperand of '%s' must be modifiable lvalue [115]
      5 
      6 /* lint1-extra-flags: -X 351 */
      7 
      8 void
      9 example(const int *const_ptr)
     10 {
     11 
     12 	/* expect+1: warning: left operand of '=' must be modifiable lvalue [115] */
     13 	*const_ptr = 3;
     14 	/* expect+1: warning: left operand of '+=' must be modifiable lvalue [115] */
     15 	*const_ptr += 1;
     16 	/* expect+1: warning: left operand of '-=' must be modifiable lvalue [115] */
     17 	*const_ptr -= 4;
     18 	/* expect+1: warning: left operand of '*=' must be modifiable lvalue [115] */
     19 	*const_ptr *= 1;
     20 	/* expect+1: warning: left operand of '/=' must be modifiable lvalue [115] */
     21 	*const_ptr /= 5;
     22 	/* expect+1: warning: left operand of '%=' must be modifiable lvalue [115] */
     23 	*const_ptr %= 9;
     24 	/* expect+1: warning: operand of 'x++' must be modifiable lvalue [115] */
     25 	(*const_ptr)++;
     26 
     27 	/* In the next example, the left operand is not an lvalue at all. */
     28 	/* expect+1: error: left operand of '=' must be lvalue [114] */
     29 	(const_ptr + 3) = const_ptr;
     30 }
     31 
     32 typedef struct {
     33 	int const member;
     34 } const_member;
     35 
     36 void take_const_member(const_member);
     37 
     38 /*
     39  * Before init.c 1.208 from 2021-08-14 and decl.c 1.221 from 2021-08-10,
     40  * lint issued a wrong "warning: left operand of '%s' must be modifiable
     41  * lvalue", even in cases where the left operand was being initialized
     42  * instead of overwritten.
     43  *
     44  * See initialization_expr_using_op, typeok_assign, has_constant_member.
     45  * See C99 6.2.5p25.
     46  */
     47 const_member
     48 initialize_const_struct_member(void)
     49 {
     50 	/* In a simple initialization, const members can be assigned. */
     51 	const_member cm1 = (const_member) { 12345 };
     52 
     53 	if (cm1.member != 0)
     54 		/* In a function call, const members can be assigned. */
     55 		take_const_member(cm1);
     56 
     57 	struct {
     58 		const_member member;
     59 	} cm2 = {
     60 	    /* In a nested initialization, const members can be assigned. */
     61 	    cm1,
     62 	};
     63 	if (cm2.member.member != 0) {
     64 	}
     65 
     66 	/* In a return statement, const members can be assigned. */
     67 	return cm1;
     68 }
     69