test/null6.c

   1 # include "bool.h"
   2
   3 typedef /*@null@*/ int *mnull;
   4
   5 extern /*@notnull@*/ mnull mnull_create (void);
   6
   7 extern int f1 (/*@notnull@*/ mnull x); /* 1. Function f1 declared with notnull ... */
   8
   9 int f (mnull x)
  10 {
  11   return *x; /* 2. Possible dereference of null pointer: *x */
  12 }
  13
  14 static /*@unused@*/ int f2 (/*@notnull@*/ mnull x)
  15 {
  16   return *x;
  17 }
  18
  19 extern /*@falsenull@*/ bool isThree (mnull x);
  20
  21 static /*@unused@*/ int f3 (/*@notnull@*/ mnull x)
  22 {
  23   if (isThree (x)) /* the parameter was missing before 2.4! */
  24     {
  25       *x = 4;
  26     }
  27   else
  28     {
  29       *x = 5;
  30     }
  31
  32   return (*x);
  33 }
  34
  35 /*@notnull@*/ mnull f4 (void)
  36 {
  37   mnull x = NULL;
  38
  39   if (x == NULL)
  40     {
  41       x = mnull_create ();
  42     }
  43
  44   return x;
  45 }
  46
  47 /*@notnull@*/ mnull f5 (void)
  48 {
  49   static /*@only@*/ mnull x = NULL;
  50
  51   if (x == NULL)
  52     {
  53       x = mnull_create ();
  54     }
  55
  56   return x;
  57 }
  58
  59 /*@notnull@*/ mnull f6 (void)
  60 {
  61   static /*@only@*/ mnull x = NULL;
  62
  63   if (x != NULL)
  64     {
  65       x = mnull_create ();
  66     }
  67
  68   return x; /* 3. Possibly null storage returned as non-null */
  69 }
  70
  71 /*@notnull@*/ mnull f7 (void)
  72 {
  73   static /*@only@*/ mnull x = NULL;
  74
  75   if (x == NULL)
  76     {
  77       x = mnull_create ();
  78     }
  79   else
  80     {
  81       x = NULL;
  82     }
  83
  84   return x; /* 4. Possibly null storage returned as non-null */
  85 }