gcc/testsuite/gcc.dg/uninit-pr59970.c

   1 /* PR tree-optimization/59970 - Bogus -Wmaybe-uninitialized at low optimization
   2    levels
   3    { dg-do compile }
   4    { dg-options "-Wall" } */
   5
   6 #pragma GCC push_options
   7 #pragma GCC optimize ("1")
   8
   9 __attribute__ ((noipa)) int
  10 d_demangle_callback_O1 (const char *mangled)
  11 {
  12   enum { DCT_TYPE, DCT_GLOBAL_DTORS } type;
  13   int dc;
  14
  15   /* Fails for -Og and -O1.  */
  16   if (mangled)
  17     type = DCT_GLOBAL_DTORS;
  18   else
  19     type = DCT_TYPE;
  20
  21   /* If both cases assign the same value, all is fine.  */
  22   switch (type)
  23     {
  24     case DCT_TYPE:
  25       dc = 0 /* 1 */;
  26       break;
  27     case DCT_GLOBAL_DTORS:
  28       dc = /* 0 */ 1;
  29       break;
  30
  31       /* If this is added, all is fine.  */
  32 #ifdef ABORT
  33     default:
  34       __builtin_unreachable ();
  35 #endif
  36     }
  37
  38   return dc;        // { dg-bogus "uninitialized" }
  39 }
  40
  41 #pragma GCC pop_options
  42
  43
  44 #pragma GCC optimize ("Og")
  45
  46 __attribute__ ((noipa)) int
  47 d_demangle_callback_Og (const char *mangled)
  48 {
  49   enum { DCT_TYPE, DCT_GLOBAL_DTORS } type;
  50   int dc;
  51
  52   /* Fails for -Og.  */
  53   /* Removing either the function call or the array dereference, it'll be like
  54      the TOGGLE1 case.  */
  55   extern int cmp (void);
  56   if (cmp () && mangled[0])
  57     type = DCT_GLOBAL_DTORS;
  58   else
  59     type = DCT_TYPE;
  60
  61   /* If both cases assign the same value, all is fine.  */
  62   switch (type)
  63     {
  64     case DCT_TYPE:
  65       dc = 0 /* 1 */;
  66       break;
  67     case DCT_GLOBAL_DTORS:
  68       dc = /* 0 */ 1;
  69       break;
  70
  71       /* If this is added, all is fine.  */
  72 #ifdef ABORT
  73     default:
  74       __builtin_unreachable ();
  75 #endif
  76     }
  77
  78   return dc;        // { dg-bogus "uninitialized" }
  79 }