text: // RUN: %clang_cc1 -fsyntax-only -verify -Wno-strict-prototypes %s
  
  // rdar: // 8125274
  static int a16[];  // expected-warning {{tentative array definition assumed to have one element}}
  
  void f16(void) {
      extern int a16[];
  }
  
  
  // PR10013: Scope of extern declarations extend past enclosing block
  extern int PR10013_x;
  int PR10013(void) {
    int *PR10013_x = 0;
    {
      extern int PR10013_x;
      extern int PR10013_x; 
    }
    
    return PR10013_x; // expected-warning{{incompatible pointer to integer conversion}}
  }
  
  static int test1_a[]; // expected-warning {{tentative array definition assumed to have one element}}
  extern int test1_a[];
  
  // rdar://13535367
  void test2declarer(void) { extern int test2_array[100]; }
  extern int test2_array[];
  int test2v = sizeof(test2_array); // expected-error {{invalid application of 'sizeof' to an incomplete type 'int[]'}}
  
  void test3declarer(void) {
    { extern int test3_array[100]; }
    extern int test3_array[];
    int x = sizeof(test3_array); // expected-error {{invalid application of 'sizeof' to an incomplete type 'int[]'}}
  }
  
  void test4(void) {
    extern int test4_array[];
    {
      extern int test4_array[100];
      int x = sizeof(test4_array); // fine
    }
    int x = sizeof(test4_array); // expected-error {{invalid application of 'sizeof' to an incomplete type 'int[]'}}
  }
  
  // Test that invalid local extern declarations of library
  // builtins behave reasonably.
  extern void abort(void); // expected-note 2 {{previous declaration is here}}
  extern float *calloc(void); // expected-warning {{incompatible redeclaration of library function}} expected-note {{is a builtin}} expected-note 2 {{previous declaration is here}}
  void test5a(void) {
    int abort(void); // expected-error {{conflicting types}}
    float *malloc(void); // expected-warning {{incompatible redeclaration of library function}} expected-note 2 {{is a builtin}}
    int *calloc(void); // expected-error {{conflicting types}}
  }
  void test5b(void) {
    int abort(void); // expected-error {{conflicting types}}
    float *malloc(void); // expected-warning {{incompatible redeclaration of library function}}
    int *calloc(void); // expected-error {{conflicting types}}
  }
  void test5c(void) {
    void (*_abort)(void) = &abort;
    void *(*_malloc)() = &malloc;
    float *(*_calloc)() = &calloc;
  }
  
  void test6(void) {
    extern int test6_array1[100];
    extern int test6_array2[100];
    void test6_fn1(int*);
    void test6_fn2(int*);
    {
      // Types are only merged from visible declarations.
      char test6_array2;
      char test6_fn2;
      {
        extern int test6_array1[];
        extern int test6_array2[];
        (void)sizeof(test6_array1); // ok
        (void)sizeof(test6_array2); // expected-error {{incomplete type}}
  
        void test6_fn1();
        void test6_fn2();
        test6_fn1(1.2); // expected-error {{passing 'double' to parameter of incompatible type 'int *'}}
        // FIXME: This is valid, but we should warn on it.
        test6_fn2(1.2);
      }
    }
  }
  