1 // RUN: %clang_cc1 -fsyntax-only -verify %s
2
3 // A program that calls for default-initialization or value-initialization of
4 // an entity of reference type is illformed. If T is a cv-qualified type, the
5 // cv-unqualified version of T is used for these definitions of
6 // zero-initialization, default-initialization, and value-initialization.
7
8 struct S { // expected-error {{implicit default constructor for 'S' must explicitly initialize the reference member}}
9 int &x; // expected-note {{declared here}} expected-error 3{{reference to type 'int' requires an initializer}}
10 };
11 S s; // expected-note {{implicit default constructor for 'S' first required here}}
f()12 S f() {
13 return S(); // expected-note {{in value-initialization of type 'S' here}}
14 }
15
16 struct T
17 : S { // expected-note 2{{in value-initialization of type 'S' here}}
18 };
19 T t = T(); // expected-note {{in value-initialization of type 'T' here}}
20
21 struct U {
22 T t[3]; // expected-note {{in value-initialization of type 'T' here}}
23 };
24 U u = U(); // expected-note {{in value-initialization of type 'U' here}}
25
26 // Ensure that we handle C++11 in-class initializers properly as an extension.
27 // In this case, there is no user-declared default constructor, so we
28 // recursively apply the value-initialization checks, but we will emit a
29 // constructor call anyway, because the default constructor is not trivial.
30 struct V {
31 int n;
32 int &r = n; // expected-warning {{C++11}}
33 };
34 V v = V(); // ok
35 struct W {
36 int n;
37 S s = { n }; // expected-warning {{C++11}}
38 };
39 W w = W(); // ok
40
41 // Ensure we're not faking this up by making the default constructor
42 // non-trivial.
43 #define static_assert(B, S) typedef int assert_failed[(B) ? 1 : -1];
44 static_assert(__has_trivial_constructor(S), "");
45 static_assert(__has_trivial_constructor(T), "");
46 static_assert(__has_trivial_constructor(U), "");
47 static_assert(!__has_trivial_constructor(V), "");
48 static_assert(!__has_trivial_constructor(W), "");
49