gcc/testsuite/gcc.dg/func-ptr-conv-1.c

   1 /* Conversions between function and object pointers are not permitted
   2    in any version of ISO C, even with casts, except for the special
   3    case of converting a null pointer constant to function pointer
   4    type.  Likewise, comparisons between function and object pointers
   5    are not permitted.  PR c/11234.  */
   6 /* Origin: Joseph Myers <jsm@polyomino.org.uk> */
   7 /* { dg-do compile } */
   8 /* { dg-options "-pedantic" } */
   9
  10 void f(void);
  11
  12 void *v1 = f; /* { dg-warning "12:pointer" "bad conversion" } */
  13 void *v2 = &f; /* { dg-warning "12:pointer" "bad conversion" } */
  14 void *v3 = (void *)f; /* { dg-warning "12:pointer" "bad conversion" } */
  15 void *v4 = (void *)&f; /* { dg-warning "12:pointer" "bad conversion" } */
  16 void *v5;
  17 char *c1 = f; /* { dg-warning "12:pointer" "bad conversion" } */
  18 char *c2 = &f; /* { dg-warning "12:pointer" "bad conversion" } */
  19 char *c3 = (char *)f; /* { dg-warning "12:pointer" "bad conversion" } */
  20 char *c4 = (char *)&f; /* { dg-warning "12:pointer" "bad conversion" } */
  21 char *c5;
  22 void (*fp)(void);
  23 int a;
  24
  25 void
  26 g(void)
  27 {
  28   v5 = f; /* { dg-warning "6:pointer" "bad conversion" } */
  29   v5 = &f; /* { dg-warning "6:pointer" "bad conversion" } */
  30   v5 = (void *)f; /* { dg-warning "8:pointer" "bad conversion" } */
  31   v5 = (void *)&f; /* { dg-warning "8:pointer" "bad conversion" } */
  32   c5 = f; /* { dg-warning "6:pointer" "bad conversion" } */
  33   c5 = &f; /* { dg-warning "6:pointer" "bad conversion" } */
  34   c5 = (char *)f; /* { dg-warning "8:pointer" "bad conversion" } */
  35   c5 = (char *)&f; /* { dg-warning "8:pointer" "bad conversion" } */
  36   fp = v5; /* { dg-warning "6:pointer" "bad conversion" } */
  37   fp = c5; /* { dg-warning "6:pointer" "bad conversion" } */
  38   fp = (void (*)(void))v5; /* { dg-warning "8:pointer" "bad conversion" } */
  39   fp = (void (*)(void))c5; /* { dg-warning "8:pointer" "bad conversion" } */
  40   (a ? f : v3); /* { dg-warning "10:pointer" "bad conversion" } */
  41   (a ? v2 : fp); /* { dg-warning "11:pointer" "bad conversion" } */
  42   /* The following are OK.  */
  43   fp = 0;
  44   fp = (void *)0;
  45   fp = 0L;
  46   fp = (void (*)(void))0;
  47   fp = (void (*)(void))(void *)0;
  48   (a ? f : 0);
  49   (a ? f : (void *)0);
  50   (a ? (void *)0 : fp);
  51   (a ? 0 : fp);
  52 }
  53
  54 /* The following are OK.  */
  55 void (*fp2)(void) = 0;
  56 void (*fp3)(void) = (void *)0;