gcc/testsuite/c-c++-common/Wpointer-compare-1.c

   1 /* PR c++/64767 */
   2 /* { dg-do compile } */
   3 /* { dg-options "-Wpointer-compare" } */
   4 /* { dg-additional-options "-std=c++03" { target c++ } } */
   5
   6 int
   7 f1 (int *p, int **q)
   8 {
   9   int r = 0;
  10
  11   r += p == '\0'; /* { dg-warning "comparison between pointer and zero character" } */
  12   r += p == L'\0'; /* { dg-warning "comparison between pointer and zero character" } */
  13   r += p != '\0'; /* { dg-warning "comparison between pointer and zero character" } */
  14   r += p != L'\0'; /* { dg-warning "comparison between pointer and zero character" } */
  15
  16   r += '\0' == p; /* { dg-warning "comparison between pointer and zero character" } */
  17   r += L'\0' == p; /* { dg-warning "comparison between pointer and zero character" } */
  18   r += '\0' != p; /* { dg-warning "comparison between pointer and zero character" } */
  19   r += L'\0' != p; /* { dg-warning "comparison between pointer and zero character" } */
  20
  21   r += q == '\0'; /* { dg-warning "comparison between pointer and zero character" } */
  22   r += q == L'\0'; /* { dg-warning "comparison between pointer and zero character" } */
  23   r += q != '\0'; /* { dg-warning "comparison between pointer and zero character" } */
  24   r += q != L'\0'; /* { dg-warning "comparison between pointer and zero character" } */
  25
  26   r += '\0' == q; /* { dg-warning "comparison between pointer and zero character" } */
  27   r += L'\0' == q; /* { dg-warning "comparison between pointer and zero character" } */
  28   r += '\0' != q; /* { dg-warning "comparison between pointer and zero character" } */
  29   r += L'\0' != q; /* { dg-warning "comparison between pointer and zero character" } */
  30
  31   return r;
  32 }
  33
  34 int
  35 f2 (int *p)
  36 {
  37   int r = 0;
  38
  39   /* Keep quiet.  */
  40   r += p == (void *) 0;
  41   r += p != (void *) 0;
  42   r += (void *) 0 == p;
  43   r += (void *) 0 != p;
  44
  45   r += p == 0;
  46   r += p != 0;
  47   r += 0 == p;
  48   r += 0 != p;
  49
  50   return r;
  51 }
  52
  53 int
  54 f3 (int *p)
  55 {
  56   int r = 0;
  57
  58   r += p == (char) 0; /* { dg-warning "comparison between pointer and zero character" } */
  59   r += p != (char) 0; /* { dg-warning "comparison between pointer and zero character" } */
  60
  61   r += (char) 0 == p; /* { dg-warning "comparison between pointer and zero character" } */
  62   r += (char) 0 != p; /* { dg-warning "comparison between pointer and zero character" } */
  63
  64   return r;
  65 }