gcc/testsuite/gcc.dg/Wstringop-overflow-60.c

   1 /* Test derived from Glibc's getifaddrs_internal.   The code could be
   2    rewritten to avoid the warning for the memcpy call but since unions
   3    are designed to have their members treated as interchangeable there
   4    isn't a whole lot to be gained from issuing one.
   5    { dg-do compile }
   6    { dg-options "-O2 -Wall" } */
   7
   8 typedef __SIZE_TYPE__ size_t;
   9
  10 extern void* memcpy (void*, const void*, size_t);
  11
  12 struct sockaddr
  13 {
  14   short sa_family;
  15   char sa_data[14];
  16 };
  17
  18 struct in_addr
  19 {
  20   int s_addr;
  21 };
  22
  23 struct in6_addr
  24 {
  25   union
  26   {
  27     char __u6_addr8[16];
  28     short __u6_addr16[8];
  29     int __u6_addr32[4];
  30   } __in6_u;
  31 };
  32
  33 struct sockaddr_in
  34 {
  35   short sin_family;
  36   short sin_port;
  37   struct in_addr sin_addr;
  38   unsigned char sin_zero[sizeof (struct sockaddr) -
  39                          (sizeof (short)) -
  40                          sizeof (short) -
  41                          sizeof (struct in_addr)];
  42 };
  43
  44 struct sockaddr_in6
  45 {
  46   short sin6_family;
  47   short sin6_port;
  48   int sin6_flowinfo;
  49   struct in6_addr sin6_addr;
  50   int sin6_scope_id;
  51 };
  52
  53 union
  54 {
  55   struct sockaddr sa;
  56   struct sockaddr_in s4;
  57   struct sockaddr_in6 s6;
  58 } u1, u2;
  59
  60 struct sockaddr *sa;
  61
  62 void test_unconditional (void *p)
  63 {
  64   sa = &u1.sa;
  65   memcpy (&((struct sockaddr_in6 *) sa)->sin6_addr, p, 16);
  66 }
  67
  68 void test_conditional (void *p, int i)
  69 {
  70   sa = i ? &u1.sa : &u2.sa;
  71   memcpy (&((struct sockaddr_in6 *) sa)->sin6_addr, p, 16);
  72 }