gcc/testsuite/c-c++-common/analyzer/pr99193-2.c

   1 /* Verify absence of false positive from -Wanalyzer-mismatching-deallocation
   2    on realloc(3).
   3    Based on https://github.com/libguestfs/libguestfs/blob/f19fd566f6387ce7e4d82409528c9dde374d25e0/df/main.c#L404
   4    which is GPLv2 or later.  */
   5
   6 /* { dg-additional-options "-Wno-analyzer-too-complex" } */
   7
   8 typedef __SIZE_TYPE__ size_t;
   9 typedef __builtin_va_list va_list;
  10
  11 #include "../../gcc.dg/analyzer/analyzer-decls.h"
  12
  13 extern void free (void *);
  14 extern void *realloc (void *__ptr, size_t __size)
  15   __attribute__ ((__nothrow__ , __leaf__))
  16   __attribute__ ((__warn_unused_result__))
  17   __attribute__ ((__alloc_size__ (2)));
  18 char *strdup (const char *)
  19   __attribute__((malloc (free)));
  20
  21 extern void error (int __status, int __errnum, const char *__format, ...)
  22      __attribute__ ((__format__ (__printf__, 3, 4)));
  23
  24 extern int errno;
  25
  26 struct drv
  27 {
  28   struct drv *next;
  29 };
  30
  31 #define EXIT_FAILURE 1
  32
  33 static char *
  34 single_drive_display_name (struct drv *)
  35 {
  36   char *result = strdup ("placeholder");
  37   if (!result)
  38     __builtin_abort ();
  39   return result;
  40 }
  41
  42 char *
  43 make_display_name (struct drv *drvs)
  44 {
  45   char *ret;
  46
  47   if (drvs->next == NULL)
  48     ret = single_drive_display_name (drvs);
  49   else {
  50     size_t pluses = 0;
  51     size_t i, len;
  52
  53     while (drvs->next != NULL) {
  54       drvs = drvs->next;
  55       pluses++;
  56     }
  57
  58     ret = single_drive_display_name (drvs);
  59     len = __builtin_strlen (ret);
  60
  61     ret = (char *) realloc (ret, len + pluses + 1); /* { dg-bogus "'free'" } */
  62     if (ret == NULL)
  63       error (EXIT_FAILURE, errno, "realloc");
  64     for (i = len; i < len + pluses; ++i)
  65       ret[i] = '+';
  66     ret[i] = '\0';
  67   }
  68
  69   return ret;
  70 }