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// PR c++/24745 : warnings for NULL constant.
// { dg-do compile }
// { dg-options "-Wpointer-arith -Wconversion " }
#include <cstddef>
int foo (void)
{
if (NULL == 1) return -1; // { dg-warning "NULL used in arithmetic" }
if (NULL > NULL) return -1; // { dg-warning "NULL used in arithmetic" }
if (NULL < NULL) return -1; // { dg-warning "NULL used in arithmetic" }
if (NULL >= 0) return -1; // { dg-warning "NULL used in arithmetic" }
if (NULL <= 0) return -1; // { dg-warning "NULL used in arithmetic" }
// Adding to the NULL pointer, which has no specific type, should
// result in a warning; the type of the resulting expression is
// actually "int", not a pointer type.
if (NULL + 1) return -1; // { dg-warning "NULL used in arithmetic" }
if (1 + NULL) return -1; // { dg-warning "NULL used in arithmetic" }
return 0;
}
int *ip;
struct S {};
typedef int S::*SPD;
typedef void (S::*SPF)(void);
SPD spd;
SPF spf;
int bar (void)
{
if (NULL) return -1;
if (!NULL) return -1;
if (!NULL == 1) return -1;
if (NULL || NULL) return -1;
if (!NULL && NULL) return -1;
if (NULL == NULL) return -1;
if (NULL != NULL) return -1;
if (NULL == 0) return -1;
if (NULL != 0) return -1;
// Subtraction of pointers is vaild, so using NULL is OK.
if (ip - NULL) return -1;
if (NULL - NULL) return -1;
// Comparing NULL with a pointer-to-member is OK.
if (NULL == spd) return -1;
if (spd == NULL) return -1;
if (NULL != spd) return -1;
if (spd != NULL) return -1;
if (NULL == spf) return -1;
if (spf == NULL) return -1;
if (NULL != spf) return -1;
if (spf != NULL) return -1;
return 0;
}
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