cxx0x-attributes.cpp revision 176edba5311f6eff0cad2631449885ddf4fbc9ea 
1// RUN: %clang_cc1 -fcxx-exceptions -fexceptions -fsyntax-only -verify -std=c++11 -Wc++14-compat %s
2
3// Need std::initializer_list
4namespace std {
5  typedef decltype(sizeof(int)) size_t;
6
7  // libc++'s implementation
8  template <class _E>
9  class initializer_list
10  {
11    const _E* __begin_;
12    size_t    __size_;
13
14    initializer_list(const _E* __b, size_t __s)
15      : __begin_(__b),
16        __size_(__s)
17    {}
18
19  public:
20    typedef _E        value_type;
21    typedef const _E& reference;
22    typedef const _E& const_reference;
23    typedef size_t    size_type;
24
25    typedef const _E* iterator;
26    typedef const _E* const_iterator;
27
28    initializer_list() : __begin_(nullptr), __size_(0) {}
29
30    size_t    size()  const {return __size_;}
31    const _E* begin() const {return __begin_;}
32    const _E* end()   const {return __begin_ + __size_;}
33  };
34}
35
36
37// Declaration syntax checks
38[[]] int before_attr;
39int [[]] between_attr;
40const [[]] int between_attr_2 = 0; // expected-error {{an attribute list cannot appear here}}
41int after_attr [[]];
42int * [[]] ptr_attr;
43int & [[]] ref_attr = after_attr;
44int & [[unknown]] ref_attr_2 = after_attr; // expected-warning {{unknown attribute 'unknown' ignored}}
45int & [[noreturn]] ref_attr_3 = after_attr; // expected-error {{'noreturn' attribute cannot be applied to types}}
46int && [[]] rref_attr = 0;
47int array_attr [1] [[]];
48alignas(8) int aligned_attr;
49[[test::valid(for 42 [very] **** '+' symbols went on a trip and had a "good"_time; the end.)]] int garbage_attr; // expected-warning {{unknown attribute 'valid' ignored}}
50[[,,,static, class, namespace,, inline, constexpr, mutable,, bitand, bitor::compl(!.*_ Cx.!U^*R),,,]] int more_garbage_attr; // expected-warning {{unknown attribute 'static' ignored}} \
51    // expected-warning {{unknown attribute 'class' ignored}} \
52    // expected-warning {{unknown attribute 'namespace' ignored}} \
53    // expected-warning {{unknown attribute 'inline' ignored}} \
54    // expected-warning {{unknown attribute 'constexpr' ignored}} \
55    // expected-warning {{unknown attribute 'mutable' ignored}} \
56    // expected-warning {{unknown attribute 'bitand' ignored}} \
57    // expected-warning {{unknown attribute 'compl' ignored}}
58[[u8"invalid!"]] int invalid_string_attr; // expected-error {{expected ']'}}
59void fn_attr () [[]];
60void noexcept_fn_attr () noexcept [[]];
61struct MemberFnOrder {
62  virtual void f() const volatile && noexcept [[]] final = 0;
63};
64struct [[]] struct_attr;
65class [[]] class_attr {};
66union [[]] union_attr;
67
68// Checks attributes placed at wrong syntactic locations of class specifiers.
69class [[]] [[]]
70  attr_after_class_name_decl [[]] [[]]; // expected-error {{an attribute list cannot appear here}}
71
72class [[]] [[]]
73 attr_after_class_name_definition [[]] [[]] [[]]{}; // expected-error {{an attribute list cannot appear here}}
74
75class [[]] c {};
76class c [[]] [[]] x;
77class c [[]] [[]] y [[]] [[]];
78class c final [(int){0}];
79
80class base {};
81class [[]] [[]] final_class
82  alignas(float) [[]] final // expected-error {{an attribute list cannot appear here}}
83  alignas(float) [[]] [[]] alignas(float): base{}; // expected-error {{an attribute list cannot appear here}}
84
85class [[]] [[]] final_class_another
86  [[]] [[]] alignas(16) final // expected-error {{an attribute list cannot appear here}}
87  [[]] [[]] alignas(16) [[]]{}; // expected-error {{an attribute list cannot appear here}}
88
89[[]] struct with_init_declarators {} init_declarator;
90[[]] struct no_init_declarators; // expected-error {{an attribute list cannot appear here}}
91template<typename> [[]] struct no_init_declarators_template; // expected-error {{an attribute list cannot appear here}}
92void fn_with_structs() {
93  [[]] struct with_init_declarators {} init_declarator;
94  [[]] struct no_init_declarators; // expected-error {{an attribute list cannot appear here}}
95}
96[[]];
97struct ctordtor {
98  [[]] ctordtor();
99  [[]] ~ctordtor();
100};
101[[]] ctordtor::ctordtor() {}
102[[]] ctordtor::~ctordtor() {}
103extern "C++" [[]] int extern_attr;
104template <typename T> [[]] void template_attr ();
105[[]] [[]] int [[]] [[]] multi_attr [[]] [[]];
106
107int comma_attr [[,]];
108int scope_attr [[foo::]]; // expected-error {{expected identifier}}
109int (paren_attr) [[]]; // expected-error {{an attribute list cannot appear here}}
110unsigned [[]] int attr_in_decl_spec; // expected-error {{an attribute list cannot appear here}}
111unsigned [[]] int [[]] const double_decl_spec = 0; // expected-error 2{{an attribute list cannot appear here}}
112class foo {
113  void const_after_attr () [[]] const; // expected-error {{expected ';'}}
114};
115extern "C++" [[]] { } // expected-error {{an attribute list cannot appear here}}
116[[]] template <typename T> void before_template_attr (); // expected-error {{an attribute list cannot appear here}}
117[[]] namespace ns { int i; } // expected-error {{an attribute list cannot appear here}} expected-note {{declared here}}
118[[]] static_assert(true, ""); //expected-error {{an attribute list cannot appear here}}
119[[]] asm(""); // expected-error {{an attribute list cannot appear here}}
120
121[[]] using ns::i; // expected-error {{an attribute list cannot appear here}}
122[[unknown]] using namespace ns; // expected-warning {{unknown attribute 'unknown' ignored}}
123[[noreturn]] using namespace ns; // expected-error {{'noreturn' attribute only applies to functions}}
124namespace [[]] ns2 {} // expected-warning {{attributes on a namespace declaration are incompatible with C++ standards before C++1z}}
125
126using [[]] alignas(4) [[]] ns::i; // expected-error {{an attribute list cannot appear here}}
127using [[]] alignas(4) [[]] foobar = int; // expected-error {{an attribute list cannot appear here}} expected-error {{'alignas' attribute only applies to}}
128
129void bad_attributes_in_do_while() {
130  do {} while (
131      [[ns::i); // expected-error {{expected ']'}} \
132                // expected-note {{to match this '['}} \
133                // expected-error {{expected expression}}
134  do {} while (
135      [[a]b ns::i); // expected-error {{expected ']'}} \
136                    // expected-note {{to match this '['}} \
137                    // expected-error {{expected expression}}
138  do {} while (
139      [[ab]ab] ns::i); // expected-error {{an attribute list cannot appear here}}
140  do {} while ( // expected-note {{to match this '('}}
141      alignas(4 ns::i; // expected-note {{to match this '('}}
142} // expected-error 2{{expected ')'}} expected-error {{expected expression}}
143
144[[]] using T = int; // expected-error {{an attribute list cannot appear here}}
145using T [[]] = int; // ok
146template<typename T> using U [[]] = T;
147using ns::i [[]]; // expected-error {{an attribute list cannot appear here}}
148using [[]] ns::i; // expected-error {{an attribute list cannot appear here}}
149using T [[unknown]] = int; // expected-warning {{unknown attribute 'unknown' ignored}}
150using T [[noreturn]] = int; // expected-error {{'noreturn' attribute only applies to functions}}
151using V = int; // expected-note {{previous}}
152using V [[gnu::vector_size(16)]] = int; // expected-error {{redefinition with different types}}
153
154auto trailing() -> [[]] const int; // expected-error {{an attribute list cannot appear here}}
155auto trailing() -> const [[]] int; // expected-error {{an attribute list cannot appear here}}
156auto trailing() -> const int [[]];
157auto trailing_2() -> struct struct_attr [[]];
158
159namespace N {
160  struct S {};
161};
162template<typename> struct Template {};
163
164// FIXME: Improve this diagnostic
165struct [[]] N::S s; // expected-error {{an attribute list cannot appear here}}
166struct [[]] Template<int> t; // expected-error {{an attribute list cannot appear here}}
167struct [[]] ::template Template<int> u; // expected-error {{an attribute list cannot appear here}}
168template struct [[]] Template<char>; // expected-error {{an attribute list cannot appear here}}
169template <> struct [[]] Template<void>;
170
171enum [[]] E1 {};
172enum [[]] E2; // expected-error {{forbids forward references}}
173enum [[]] E1;
174enum [[]] E3 : int;
175enum [[]] {
176  k_123 [[]] = 123 // expected-warning {{attributes on an enumerator declaration are incompatible with C++ standards before C++1z}}
177};
178enum [[]] E1 e; // expected-error {{an attribute list cannot appear here}}
179enum [[]] class E4 { }; // expected-error {{an attribute list cannot appear here}}
180enum struct [[]] E5;
181
182struct S {
183  friend int f [[]] (); // expected-FIXME{{an attribute list cannot appear here}}
184  friend int f1 [[noreturn]] (); //expected-error{{an attribute list cannot appear here}}
185  friend int f2 [[]] [[noreturn]] () {}
186  [[]] friend int g(); // expected-error{{an attribute list cannot appear here}}
187  [[]] friend int h() {
188  }
189  [[]] friend int f3(), f4(), f5(); // expected-error{{an attribute list cannot appear here}}
190  friend int f6 [[noreturn]] (), f7 [[noreturn]] (), f8 [[noreturn]] (); // expected-error3 {{an attribute list cannot appear here}}
191  friend class [[]] C; // expected-error{{an attribute list cannot appear here}}
192  [[]] friend class D; // expected-error{{an attribute list cannot appear here}}
193  [[]] friend int; // expected-error{{an attribute list cannot appear here}}
194};
195template<typename T> void tmpl(T) {}
196template void tmpl [[]] (int); // expected-FIXME {{an attribute list cannot appear here}}
197template [[]] void tmpl(char); // expected-error {{an attribute list cannot appear here}}
198template void [[]] tmpl(short);
199
200// Argument tests
201alignas int aligned_no_params; // expected-error {{expected '('}}
202alignas(i) int aligned_nonconst; // expected-error {{'aligned' attribute requires integer constant}} expected-note {{read of non-const variable 'i'}}
203
204// Statement tests
205void foo () {
206  [[]] ;
207  [[]] { }
208  [[]] if (0) { }
209  [[]] for (;;);
210  [[]] do {
211    [[]] continue;
212  } while (0);
213  [[]] while (0);
214
215  [[]] switch (i) {
216    [[]] case 0:
217    [[]] default:
218      [[]] break;
219  }
220
221  [[]] goto there;
222  [[]] there:
223
224  [[]] try {
225  } [[]] catch (...) { // expected-error {{an attribute list cannot appear here}}
226  }
227  struct S { int arr[2]; } s;
228  (void)s.arr[ [] { return 0; }() ]; // expected-error {{C++11 only allows consecutive left square brackets when introducing an attribute}}
229  int n = __builtin_offsetof(S, arr[ [] { return 0; }() ]); // expected-error {{C++11 only allows consecutive left square brackets when introducing an attribute}}
230
231  void bar [[noreturn]] ([[]] int i, [[]] int j);
232  using FuncType = void ([[]] int);
233  void baz([[]]...); // expected-error {{expected parameter declarator}}
234
235  [[]] return;
236}
237
238template<typename...Ts> void variadic() {
239  void bar [[noreturn...]] (); // expected-error {{attribute 'noreturn' cannot be used as an attribute pack}}
240}
241
242// Expression tests
243void bar () {
244  // FIXME: GCC accepts [[gnu::noreturn]] on a lambda, even though it appertains
245  // to the operator()'s type, and GCC does not otherwise accept attributes
246  // applied to types. Use that to test this.
247  [] () [[gnu::noreturn]] { return; } (); // expected-warning {{attribute 'noreturn' ignored}} FIXME-error {{should not return}}
248  [] () [[gnu::noreturn]] { throw; } (); // expected-warning {{attribute 'noreturn' ignored}}
249  new int[42][[]][5][[]]{};
250}
251
252// Condition tests
253void baz () {
254  if ([[unknown]] bool b = true) { // expected-warning {{unknown attribute 'unknown' ignored}}
255    switch ([[unknown]] int n { 42 }) { // expected-warning {{unknown attribute 'unknown' ignored}}
256    default:
257      for ([[unknown]] int n = 0; [[unknown]] char b = n < 5; ++b) { // expected-warning 2{{unknown attribute 'unknown' ignored}}
258      }
259    }
260  }
261  int x;
262  // An attribute can be applied to an expression-statement, such as the first
263  // statement in a for. But it can't be applied to a condition which is an
264  // expression.
265  for ([[]] x = 0; ; ) {} // expected-error {{an attribute list cannot appear here}}
266  for (; [[]] x < 5; ) {} // expected-error {{an attribute list cannot appear here}}
267  while ([[]] bool k { false }) {
268  }
269  while ([[]] true) { // expected-error {{an attribute list cannot appear here}}
270  }
271  do {
272  } while ([[]] false); // expected-error {{an attribute list cannot appear here}}
273
274  for ([[unknown]] int n : { 1, 2, 3 }) { // expected-warning {{unknown attribute 'unknown' ignored}}
275  }
276}
277
278enum class __attribute__((visibility("hidden"))) SecretKeepers {
279  one, /* rest are deprecated */ two, three
280};
281enum class [[]] EvenMoreSecrets {};
282
283namespace arguments {
284  void f[[gnu::format(printf, 1, 2)]](const char*, ...);
285  void g() [[unknown::foo(ignore arguments for unknown attributes, even with symbols!)]]; // expected-warning {{unknown attribute 'foo' ignored}}
286  [[deprecated("with argument")]] int i;
287}
288
289// Forbid attributes on decl specifiers.
290unsigned [[gnu::used]] static int [[gnu::unused]] v1; // expected-error {{'unused' attribute cannot be applied to types}} \
291           expected-error {{an attribute list cannot appear here}}
292typedef [[gnu::used]] unsigned long [[gnu::unused]] v2; // expected-error {{'unused' attribute cannot be applied to types}} \
293          expected-error {{an attribute list cannot appear here}}
294int [[carries_dependency]] foo(int [[carries_dependency]] x); // expected-error 2{{'carries_dependency' attribute cannot be applied to types}}
295
296// Forbid [[gnu::...]] attributes on declarator chunks.
297int *[[gnu::unused]] v3; // expected-warning {{attribute 'unused' ignored}}
298int v4[2][[gnu::unused]]; // expected-warning {{attribute 'unused' ignored}}
299int v5()[[gnu::unused]]; // expected-warning {{attribute 'unused' ignored}}
300
301[[attribute_declaration]]; // expected-warning {{unknown attribute 'attribute_declaration' ignored}}
302[[noreturn]]; // expected-error {{'noreturn' attribute only applies to functions}}
303[[carries_dependency]]; // expected-error {{'carries_dependency' attribute only applies to functions, methods, and parameters}}
304
305class A {
306  A([[gnu::unused]] int a);
307};
308A::A([[gnu::unused]] int a) {}
309
310namespace GccConst {
311  // GCC's tokenizer treats const and __const as the same token.
312  [[gnu::const]] int *f1();
313  [[gnu::__const]] int *f2();
314  [[gnu::__const__]] int *f3();
315  void f(const int *);
316  void g() { f(f1()); f(f2()); }
317  void h() { f(f3()); }
318}
319
320namespace GccASan {
321  __attribute__((no_address_safety_analysis)) void f1();
322  __attribute__((no_sanitize_address)) void f2();
323  [[gnu::no_address_safety_analysis]] void f3();
324  [[gnu::no_sanitize_address]] void f4();
325}
326
327namespace {
328  [[deprecated]] void bar();
329  [[deprecated("hello")]] void baz();
330  [[deprecated()]] void foo(); // expected-error {{parentheses must be omitted if 'deprecated' attribute's argument list is empty}}
331  [[gnu::deprecated()]] void quux();
332}
333