test/null1.c

   1 # include "bool.h"
   2
   3 void g(/*@temp@*/ int *y);
   4
   5 /*@truenull@*/ bool ptrpred (/*@out@*/ /*@null@*/ int *x)
   6 {
   7   return (x == NULL); /* new error detected by out undef */
   8 }
   9
  10 /*@only@*/ int *f(/*@null@*/ int *x)
  11 {
  12   int *y = (int *)malloc (sizeof (int));
  13   int *z;
  14   int *z2;
  15   int *z3;
  16   int *z4;
  17   int *z5;
  18
  19   if (!x) { return x; /* 1. Unqualified storage returned as only: x,
  20                       ** 2. Possibly null storage returned as non-null: x
  21                       ** 3. Fresh storage y not released before return
  22                       */
  23           }
  24
  25   z = (int *) malloc (sizeof (int));
  26   z2 = (int *)malloc (sizeof (int));
  27   z3 = (int *)malloc (sizeof (int));
  28
  29   *x = 7;
  30
  31   *y = 3; /* 4. Possible dereference of null pointer: *y */
  32   free (y);
  33
  34   g(z);   /* 5. Possibly null storage passed as non-null param: z
  35           ** 6. Passed storage z not completely defined (allocated only): z
  36           */
  37   if (z) { *z = 3; } /* okay */
  38
  39   if (!z) { *z = 3; } /* 7. Possible dereference of null pointer: *z */
  40   else { *z = 4; }    /* okay */
  41
  42   z4 = (int *)malloc (sizeof (int));
  43   if (z4 == NULL) { *z4 = 3; } /* 8. Possible dereference of null pointer: *z4 */
  44   else { free (z4); } /* [ not any more: 12. Clauses exit... ] */
  45
  46   if (!(z2 != NULL)) { *z2 = 3; } /* 9. Possible dereference of null pointer: *z2 */
  47
  48   if (z3 != NULL) { *z3 = 5; /* okay */ }
  49   else { *z3 = 3; } /* 10. Possible dereference of null pointer: *z3 */
  50   if (z2) free (z2);
  51   z2 = (int *)malloc (sizeof (int));
  52
  53   if (z2 != NULL) { *z2 = 5; } ;
  54
  55   *z2 = 7; /* 11. Possible dereference of null pointer: *z2 */
  56
  57   z5 = (int *) malloc (sizeof (int));
  58
  59   if (ptrpred(z5)) { *z5 = 3; }  /* 12. Possible dereference of null pointer: *z5 */
  60   if (!ptrpred(z5)) { *z5 = 3; }
  61
  62   if (ptrpred(z5)) { *z5 = 3; }
  63   else { free (z5); }
  64
  65   free (z2);
  66
  67   return z; /* 13. Fresh storage z3 not released */
  68 }
  69
  70
  71