1 // RUN: %clang_cc1 -fsyntax-only -verify %s
2 
3 // This is a test for an egregious hack in Clang that works around
4 // issues with GCC's evolution. libstdc++ 4.2.x uses __is_pod as an
5 // identifier (to declare a struct template like the one below), while
6 // GCC 4.3 and newer make __is_pod a keyword. Clang treats __is_pod as
7 // a keyword *unless* it is introduced following the struct keyword.
8 
9 template<typename T>
10 struct __is_pod { // expected-warning {{keyword '__is_pod' will be made available as an identifier}}
11   __is_pod() {}
12 };
13 
14 __is_pod<int> ipi;
15 
16 // Ditto for __is_same.
17 template<typename T>
18 struct __is_same { // expected-warning {{keyword '__is_same' will be made available as an identifier}}
19 };
20 
21 __is_same<int> isi;
22 
23 // Another, similar egregious hack for __is_signed, which is a type
24 // trait in Embarcadero's compiler but is used as an identifier in
25 // libstdc++.
26 struct test_is_signed {
27   static const bool __is_signed = true; // expected-warning {{keyword '__is_signed' will be made available as an identifier}}
28 };
29 
30 bool check_signed = test_is_signed::__is_signed;
31 
32 template<bool B> struct must_be_true {};
33 template<> struct must_be_true<false>;
34 
35 void foo() {
36   bool b = __is_pod(int);
37   must_be_true<__is_pod(int)> mbt;
38 }
39 
40 // expected-warning@+1 {{declaration does not declare anything}}
41 struct // expected-error {{declaration of anonymous struct must be a definition}}
42 #pragma pack(pop)
43     S {
44 };
45 
46 #if !__has_feature(is_pod)
47 #  error __is_pod should still be available.
48 #endif
49