gcc/testsuite/gcc.dg/Wstringop-overflow-14.c

   1 /* Test to verify that past-the-end multibyte writes via lvalues of wider
   2    types than char are diagnosed.
   3    { dg-do compile }
   4    { dg-require-effective-target int32plus }
   5    { dg-options "-O2 -Wall" } */
   6
   7 typedef __INT16_TYPE__  int16_t;
   8 typedef __INT32_TYPE__  int32_t;
   9 typedef __INT64_TYPE__  int64_t;
  10 typedef __SIZE_TYPE__   size_t;
  11
  12 void* memcpy (void*, const void*, size_t);
  13 char* strcpy (char*, const char*);
  14
  15 char a4[4], a8[8], a16[16];
  16
  17 const char s4[] = "1234";
  18 const char t4[] = "4321";
  19
  20 void test_memcpy_cond (int i)
  21 {
  22   char *p = a4 + 1;
  23   const char *q = i ? s4 : t4;
  24   memcpy (p, q, 4);         // { dg-warning "writing 4 bytes into a region of size 3" }
  25 }
  26
  27
  28 void test_int16 (void)
  29 {
  30   char *p = a4 + 1;
  31   *(int16_t*)p = 0;
  32   *(int16_t*)(p + 2) = 0;   // { dg-warning "writing 2 bytes into a region of size 1" }
  33 }
  34
  35
  36 void test_int32 (void)
  37 {
  38   char *p = a8 + 3;
  39   *(int32_t*)p = 0;
  40   *(int32_t*)(p + 2) = 0;   // { dg-warning "writing 4 bytes into a region of size 3" }
  41 }
  42
  43
  44 void test_int64 (void)
  45 {
  46   char *p = a16 + 5;
  47   *(int64_t*)p = 0;
  48   *(int64_t*)(p + 5) = 0;   // { dg-warning "writing 8 bytes into a region of size 6" }
  49 }