test/Sema/empty1.c

// RUN: %clang_cc1 %s -fsyntax-only -verify -Wc++-compat

struct emp_1 { // expected-warning {{empty struct has size 0 in C, size 1 in C++}}
};

union emp_2 { // expected-warning {{empty union has size 0 in C, size 1 in C++}}
};

struct emp_3 { // expected-warning {{struct with only bit-fields of width 0 has size 0 in C, size 1 in C++}}
  int : 0;
};

union emp_4 { // expected-warning {{union with only bit-fields of width 0 has size 0 in C, size 1 in C++}}
  int : 0;
};

struct emp_5 { // expected-warning {{struct with only bit-fields of width 0 has size 0 in C, size 1 in C++}}
  int : 0;
  int : 0;
};

union emp_6 { // expected-warning {{union with only bit-fields of width 0 has size 0 in C, size 1 in C++}}
  int : 0;
  int : 0;
};