gcc/testsuite/c-c++-common/Wuse-after-free-3.c

   1 /* Exercise -Wuse-after-free with user-defined deallocators.
   2    { dg-do compile }
   3    { dg-options "-O0 -Wall" } */
   4
   5 typedef __SIZE_TYPE__ size_t;
   6
   7 #if __cplusplus
   8 #  define EXTERN_C extern "C"
   9 #else
  10 #  define EXTERN_C extern
  11 #endif
  12
  13 #define A(...) __attribute__ ((malloc (__VA_ARGS__)))
  14
  15 EXTERN_C void free (void *);
  16 EXTERN_C void* realloc (void *, size_t);
  17
  18 typedef struct List { struct List *next; } List;
  19
  20 // User-defined allocator/deallocator just like like realloc and free.
  21 extern                     void  list_free (List *);
  22 extern                     List* list_realloc (size_t, List *);
  23 extern A (list_realloc, 2) List* list_realloc (size_t, List *);
  24 extern A (list_free, 1)    List* list_realloc (size_t, List *);
  25
  26
  27 void sink (void *);
  28
  29 extern int ei;
  30 extern List *elp, *elpa[];
  31
  32 void nowarn_list_free (struct List *lp)
  33 {
  34   {
  35     list_free (lp);
  36     lp = 0;
  37     sink (lp);
  38   }
  39   {
  40     list_free (elp);
  41     elp = 0;
  42     sink (elp);
  43   }
  44   {
  45     list_free (elpa[0]);
  46     elpa[0] = 0;
  47     sink (elpa[0]);
  48   }
  49   {
  50     void *vp = elpa[0];
  51     list_free (elpa[0]);
  52     sink (vp);
  53   }
  54   {
  55     List *p = elpa[1];
  56     if (ei & 1)
  57       list_free (p);
  58     if (ei & 2)
  59       sink (p);
  60   }
  61   {
  62     struct List *next = lp->next;
  63     list_free (lp);
  64     list_free (next);
  65   }
  66 }
  67
  68
  69 void nowarn_list_free_list (List *head)
  70 {
  71   for (List *p = head, *q; p; p = q)
  72     {
  73       q = p->next;
  74       list_free (p);
  75     }
  76 }
  77
  78 void warn_list_free_list (List *head)
  79 {
  80   List *p = head;
  81   for (; p; p = p->next)      // { dg-warning "\\\[-Wuse-after-free" }
  82     list_free (p);            // { dg-message "call to '\(void \)?list_free\(\\(List\\*\\)\)?'" "note" }
  83 }