chibicc/test/bitfield.c

#include "test.h"

struct {
  char a;
  int b : 5;
  int c : 10;
} g45 = {1, 2, 3}, g46={};

int main() {
  ASSERT(4, sizeof(struct {int x:1; }));
  ASSERT(8, sizeof(struct {long x:1; }));

  struct bit1 {
    short a;
    char b;
    int c : 2;
    int d : 3;
    int e : 3;
  };

  ASSERT(4, sizeof(struct bit1));
  ASSERT(1, ({ struct bit1 x; x.a=1; x.b=2; x.c=3; x.d=4; x.e=5; x.a; }));
  ASSERT(1, ({ struct bit1 x={1,2,3,4,5}; x.a; }));
  ASSERT(2, ({ struct bit1 x={1,2,3,4,5}; x.b; }));
  ASSERT(-1, ({ struct bit1 x={1,2,3,4,5}; x.c; }));
  ASSERT(-4, ({ struct bit1 x={1,2,3,4,5}; x.d; }));
  ASSERT(-3, ({ struct bit1 x={1,2,3,4,5}; x.e; }));

  ASSERT(1, g45.a);
  ASSERT(2, g45.b);
  ASSERT(3, g45.c);

  ASSERT(0, g46.a);
  ASSERT(0, g46.b);
  ASSERT(0, g46.c);

  typedef struct {
    int a : 10;
    int b : 10;
    int c : 10;
  } T3;

  ASSERT(1, ({ T3 x={1,2,3}; x.a++; }));
  ASSERT(2, ({ T3 x={1,2,3}; x.b++; }));
  ASSERT(3, ({ T3 x={1,2,3}; x.c++; }));

  ASSERT(2, ({ T3 x={1,2,3}; ++x.a; }));
  ASSERT(3, ({ T3 x={1,2,3}; ++x.b; }));
  ASSERT(4, ({ T3 x={1,2,3}; ++x.c; }));

  ASSERT(4, sizeof(struct {int a:3; int c:1; int c:5;}));
  ASSERT(8, sizeof(struct {int a:3; int:0; int c:5;}));
  ASSERT(4, sizeof(struct {int a:3; int:0;}));

  printf("OK\n");
  return 0;
}