gcc/testsuite/gcc.dg/Wstringop-overflow-2.c

   1 /* PR tree-optimization/83508 - c-c++-common/Wrestrict.c fails since r255836
   2    Test to verify that only one of -Wrestrict and -Wstringop-overflow is
   3    issued for a problem where either would be appropriate.
   4    { dg-do compile }
   5    { dg-options "-O2 -Wrestrict -Wstringop-overflow" } */
   6
   7 #define DIFF_MAX __PTRDIFF_MAX__
   8
   9 typedef __PTRDIFF_TYPE__ ptrdiff_t;
  10 typedef __SIZE_TYPE__ size_t;
  11
  12 void sink (void*);
  13
  14 void f (ptrdiff_t i, size_t n)
  15 {
  16   if (i < DIFF_MAX - 2 || DIFF_MAX - 1 > i)
  17     i = DIFF_MAX - 2;
  18
  19   if (n < 4 || 5 < n)
  20     n = 4;
  21
  22   char a[8] = "012";
  23
  24   /* The following could very well be diagnosed by -Wstringop-overflow
  25      instead but there's no way to verify that only one of the two
  26      warnings is issued and the choice of -Wrestrict simply reflects
  27      the fact that -Wrestrict runs before -Wstringop-overflow.  */
  28   __builtin_strncpy (a + i, a, n);   /* { dg-warning "\\\[-Wrestrict]" } */
  29   sink (a);
  30 }