empty-class-layout.cpp revision 7e41038723bf77132674f55b12f60e24e5473b33 
1// RUN: clang-cc -triple x86_64-unknown-unknown %s -fsyntax-only -verify
2
3#define SA(n, p) int a##n[(p) ? 1 : -1]
4
5struct A { int a; };
6SA(0, sizeof(A) == 4);
7
8struct B { };
9SA(1, sizeof(B) == 1);
10
11struct C : A, B { };
12SA(2, sizeof(C) == 4);
13
14struct D { };
15struct E : D { };
16struct F : E { };
17
18struct G : E, F { };
19SA(3, sizeof(G) == 2);
20
21struct Empty { Empty(); };
22
23struct I : Empty {
24  Empty e;
25};
26SA(4, sizeof(I) == 2);
27
28struct J : Empty {
29  Empty e[2];
30};
31SA(5, sizeof(J) == 3);
32
33template<int N> struct Derived : Empty, Derived<N - 1> {
34};
35template<> struct Derived<0> : Empty { };
36
37struct S1 : virtual Derived<10> {
38  Empty e;
39};
40SA(6, sizeof(S1) == 24);
41
42struct S2 : virtual Derived<10> {
43  Empty e[2];
44};
45SA(7, sizeof(S2) == 24);
46
47struct S3 {
48  Empty e;
49};
50
51struct S4 : Empty, S3 {
52};
53SA(8, sizeof(S4) == 2);
54
55struct S5 : S3, Empty {};
56SA(9, sizeof(S5) == 2);
57
58struct S6 : S5 { };
59SA(10, sizeof(S6) == 2);
60
61struct S7 : Empty {
62  void *v;
63};
64SA(11, sizeof(S7) == 8);
65