gcc/testsuite/g++.dg/warn/Wconversion-null-2.C

// { dg-do link  }
// { dg-options "" }

#include <cstddef>

void g(int) {}
void g(long) {}
void g(long long) {}
#ifdef __MSP430X_LARGE__
void g(__int20) {}
#endif
extern void g(void*);

template <int I>
void h() {}

void k(int) {}

template <class T>
void l(T);

template <>
void l(int) {}

template <>
void l(long) {}

template <>
void l(long long) {}

#ifdef __MSP430X_LARGE__
template <>
void l(__int20) {}
#endif

void warn_for_NULL()
{
  int i = NULL; // { dg-warning "" } converting NULL to non-pointer type
  float z = NULL; // { dg-warning "" } converting NULL to non-pointer type
  int a[2];

  i != NULL; // { dg-warning "" } NULL used in arithmetic
  NULL != z; // { dg-warning "" } NULL used in arithmetic
  k != NULL; // No warning: decay conversion
  NULL != a; // Likewise.
  -NULL;     // { dg-warning "" } converting NULL to non-pointer type
  +NULL;     // { dg-warning "" } converting NULL to non-pointer type
  ~NULL;     // { dg-warning "" } converting NULL to non-pointer type
  a[NULL] = 3; // { dg-warning "" } converting NULL to non-pointer-type
  i = NULL;  // { dg-warning "" } converting NULL to non-pointer type
  z = NULL;  // { dg-warning "" } converting NULL to non-pointer type
  k(NULL);   // { dg-warning "" } converting NULL to int
  g(NULL);   // { dg-warning "" } converting NULL to int
  h<NULL>(); // No warning: NULL bound to integer template parameter
  l(NULL);   // No warning: NULL is used to implicitly instantiate the template
  NULL && NULL; // No warning: converting NULL to bool is OK
}

void warn_for___null()
{
  int i = __null; // { dg-warning "" } converting __null to non-pointer type
  float z = __null; // { dg-warning "" } converting __null to non-pointer type
  int a[2];

  i != __null; // { dg-warning "" } __null used in arithmetic
  __null != z; // { dg-warning "" } __null used in arithmetic
  k != __null; // No warning: decay conversion
  __null != a; // Likewise.
  -__null;     // { dg-warning "" } converting __null to non-pointer type
  +__null;     // { dg-warning "" } converting __null to non-pointer type
  ~__null;     // { dg-warning "" } converting __null to non-pointer type
  a[__null] = 3; // { dg-warning "" } converting __null to non-pointer-type
  i = __null;  // { dg-warning "" } converting __null to non-pointer type
  z = __null;  // { dg-warning "" } converting __null to non-pointer type
  k(__null);   // { dg-warning "" } converting __null to int
  g(__null);   // { dg-warning "" } converting __null to int
  h<__null>(); // No warning: __null bound to integer template parameter
  l(__null);   // No warning: __null is used to implicitly instantiate the template
  __null && __null; // No warning: converting NULL to bool is OK
}

int main()
{
  warn_for_NULL();
  warn_for___null();
}