gcc/testsuite/gcc.dg/pack-test-4.c

   1 /* PR c/11885
   2    Bug: flag4 was allocated into the same byte as the other flags.
   3    { dg-options "" }
   4    { dg-do run } */
   5
   6 typedef unsigned char uint8_t;
   7
   8 typedef struct {
   9     uint8_t flag1:2;
  10     uint8_t flag2:1;
  11     uint8_t flag3:1;
  12
  13     uint8_t flag4;
  14
  15 } __attribute__ ((packed)) MyType;
  16
  17 int main (void)
  18 {
  19   MyType a;
  20   MyType *b = &a;
  21
  22   b->flag1 = 0;
  23   b->flag2 = 0;
  24   b->flag3 = 0;
  25
  26   b->flag4 = 0;
  27
  28   b->flag4++;
  29
  30   if (b->flag1 != 0)
  31     abort ();
  32 }