gcc/testsuite/gcc.dg/uninit-4-O0.c

   1 /* Spurious uninit variable warnings, case 4.
   2    Simplified version of cppexp.c (cpp_parse_expr).
   3
   4    This one is really fragile, it gets it right if you take out case
   5    1, or if the structure is replaced by an int, or if the structure
   6    has fewer members (!) */
   7
   8 /* { dg-do compile } */
   9 /* { dg-options "-Wuninitialized" } */
  10
  11 extern void abort (void);
  12
  13 struct operation {
  14     short op;
  15     char rprio;
  16     char flags;
  17     char unsignedp;
  18     long value;
  19 };
  20
  21 extern struct operation cpp_lex (void);
  22
  23 void
  24 cpp_parse_expr (void)
  25 {
  26   int rprio; /* { dg-bogus "rprio" "uninitialized variable warning PR19833" } */
  27   struct operation op;
  28
  29   for (;;)
  30     {
  31       op = cpp_lex ();
  32
  33       switch (op.op)
  34         {
  35         case 0:
  36           break;
  37         case 1:
  38           return;
  39         case 2:
  40           rprio = 1;
  41           break;
  42         default:
  43           return;
  44         }
  45
  46       if (op.op == 0)
  47         return;
  48
  49       if (rprio != 1)
  50         abort();
  51     }
  52 }