gcc/testsuite/gcc.dg/Wreturn-local-addr-5.c

   1 /* PR c/71924 - missing -Wreturn-local-addr returning alloca result
   2    { dg-do compile }
   3    { dg-options "-O2 -Wall" } */
   4
   5 void sink (void*);
   6
   7 void* loop_idx (int x)
   8 {
   9   char a[32];       /* { dg-message "declared here" } */
  10   char *p = a;
  11
  12   sink (a);
  13
  14   int i;
  15   for (i = 0; i != 32; ++i)
  16     if (p[i] == x)
  17       break;
  18
  19   p = i < 32 ? &p[i] : 0;
  20   return p;  /* { dg-warning "may return address of local variable" } */
  21 }
  22
  23
  24 void* loop_ptr (int i, int x)
  25 {
  26   char a[32];       /* { dg-message "declared here" } */
  27   char *p;
  28
  29   sink (a);
  30
  31   /* The warning for the statement below would ideally be a "returns"
  32      because it definitely returns the address of a, but when both
  33      returns get merged into one we end up with a "may return".  */
  34   for (p = a; *p; ++p)
  35     if (*p == x)
  36       return p;     /* { dg-warning "(returns|may return) address of local variable" "missing location" { xfail *-*-* } } */
  37   /* { dg-warning "(returns|may return) address of local variable" "pr90735" { target *-*-* } 0 } */
  38
  39   return 0;
  40 }