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Elixir Cross Referencer

// RUN: %clang_cc1 -triple i686-apple-darwin9 %s -fsyntax-only -verify
// expected-no-diagnostics

#include <stddef.h>

#pragma pack(4)

// Baseline
struct s0 {
  char f0;
  int  f1;
};
extern int a0[offsetof(struct s0, f1) == 4 ? 1 : -1];

#pragma pack(push, 2)
struct s1 {
  char f0;
  int  f1;
};
extern int a1[offsetof(struct s1, f1) == 2 ? 1 : -1];
#pragma pack(pop)

#pragma pack(1)
struct s3_0 {
  char f0;
  int f1;
};
#pragma pack()
struct s3_1 {
  char f0;
  int f1;
};
extern int a3_0[offsetof(struct s3_0, f1) == 1 ? 1 : -1];
extern int a3_1[offsetof(struct s3_1, f1) == 4 ? 1 : -1];

// pack(0) is like pack()
#pragma pack(1)
struct s4_0 {
  char f0;
  int f1;
};
#pragma pack(0)
struct s4_1 {
  char f0;
  int f1;
};
extern int a4_0[offsetof(struct s4_0, f1) == 1 ? 1 : -1];
extern int a4_1[offsetof(struct s4_1, f1) == 4 ? 1 : -1];

void f() {
  #pragma pack(push, 2)
  struct s5_0 {
    char f0;
    struct s2_4_0 { 
      int f0;
    } f1;
  };
  #pragma pack(pop)
  extern int s5_0[offsetof(struct s5_0, f1) == 2 ? 1 : -1];
}