gcc/testsuite/gcc.dg/uninit-20.c

   1 /* Spurious uninitialized variable warnings, from gdb */
   2 /* { dg-do compile } */
   3 /* { dg-options "-O2 -Wuninitialized" } */
   4 struct os { struct o *o; };
   5 struct o { struct o *next; struct os *se; };
   6 void f(struct o *o){
   7   struct os *s;
   8   if(o) s = o->se;
   9   while(o && s == o->se){
  10     s++; // here `o' is non-zero and thus s is initialized
  11     s == o->se  // `?' is essential, `if' does not trigger the warning
  12       ? (o = o->next, o ? s = o->se : 0)
  13       : 0;
  14   }
  15 }
  16
  17
  18