1 // RUN: %clang_cc1 %s -fsyntax-only -Wno-strict-prototypes -verify -pedantic -std=c11
2
3 __auto_type a = 5; // expected-warning {{'__auto_type' is a GNU extension}}
4 __extension__ __auto_type a1 = 5;
5 #pragma clang diagnostic ignored "-Wgnu-auto-type"
6 __auto_type b = 5.0;
7 __auto_type c = &b;
8 __auto_type d = (struct {int a;}) {5};
9 _Static_assert(__builtin_types_compatible_p(__typeof(a), int), "");
10 __auto_type e = e; // expected-error {{variable 'e' declared with deduced type '__auto_type' cannot appear in its own initializer}}
11
12 struct s { __auto_type a; }; // expected-error {{'__auto_type' not allowed in struct member}}
13
14 __auto_type f = 1, g = 1.0; // expected-error {{'__auto_type' deduced as 'int' in declaration of 'f' and deduced as 'double' in declaration of 'g'}}
15
h()16 __auto_type h() {} // expected-error {{'__auto_type' not allowed in function return type}}
17
i()18 int i() {
19 struct bitfield { int field:2; };
20 __auto_type j = (struct bitfield){1}.field; // expected-error {{cannot pass bit-field as __auto_type initializer in C}}
21
22 }
23
k(l)24 int k(l)
25 __auto_type l; // expected-error {{'__auto_type' not allowed in K&R-style function parameter}}
26 {}
27
Issue53652(void)28 void Issue53652(void) {
29 // Ensure that qualifiers all work the same way as GCC.
30 const __auto_type cat = a;
31 const __auto_type pcat = &a;
32 volatile __auto_type vat = a;
33 volatile __auto_type pvat = &a;
34 restrict __auto_type rat = &a;
35 _Atomic __auto_type aat1 = a;
36 _Atomic __auto_type paat = &a;
37
38 // GCC does not accept this either, for the same reason.
39 _Atomic(__auto_type) aat2 = a; // expected-error {{'__auto_type' not allowed here}} \
40 // expected-warning {{type specifier missing, defaults to 'int'}}
41
42 // Ensure the types are what we expect them to be, regardless of order we
43 // pass the types.
44 _Static_assert(__builtin_types_compatible_p(__typeof(cat), const int), "");
45 _Static_assert(__builtin_types_compatible_p(const int, __typeof(cat)), "");
46 _Static_assert(__builtin_types_compatible_p(__typeof(pcat), int *const), "");
47 _Static_assert(__builtin_types_compatible_p(int *const, __typeof(pcat)), "");
48 _Static_assert(__builtin_types_compatible_p(__typeof(vat), volatile int), "");
49 _Static_assert(__builtin_types_compatible_p(volatile int, __typeof(vat)), "");
50 _Static_assert(__builtin_types_compatible_p(__typeof(pvat), int *volatile), "");
51 _Static_assert(__builtin_types_compatible_p(int *volatile, __typeof(pvat)), "");
52 _Static_assert(__builtin_types_compatible_p(__typeof(rat), int *restrict), "");
53 _Static_assert(__builtin_types_compatible_p(int *restrict, __typeof(rat)), "");
54 _Static_assert(__builtin_types_compatible_p(__typeof(aat1), _Atomic int), "");
55 _Static_assert(__builtin_types_compatible_p(_Atomic int, __typeof(aat1)), "");
56 _Static_assert(__builtin_types_compatible_p(__typeof(paat), _Atomic(int *)), "");
57 _Static_assert(__builtin_types_compatible_p(_Atomic(int *), __typeof(paat)), "");
58
59 // Ensure the types also work in generic selection expressions. Remember, the
60 // type of the expression argument to _Generic is treated as-if it undergoes
61 // lvalue to rvalue conversion, which drops qualifiers. We're making sure the
62 // use of __auto_type doesn't impact that.
63 (void)_Generic(cat, int : 0);
64 (void)_Generic(pcat, int * : 0);
65 (void)_Generic(vat, int : 0);
66 (void)_Generic(pvat, int * : 0);
67 (void)_Generic(rat, int * : 0);
68 (void)_Generic(aat1, int : 0);
69 (void)_Generic(paat, int * : 0);
70
71 // Ensure that trying to merge two different __auto_type types does not
72 // decide that they are both the same type when they're actually different,
73 // and that we reject when the types are the same.
74 __auto_type i = 12;
75 __auto_type f = 1.2f;
76 (void)_Generic(a, __typeof__(i) : 0, __typeof__(f) : 1);
77 (void)_Generic(a,
78 __typeof__(i) : 0, // expected-note {{compatible type 'typeof (i)' (aka 'int') specified here}}
79 __typeof__(a) : 1); // expected-error {{type 'typeof (a)' (aka 'int') in generic association compatible with previously specified type 'typeof (i)' (aka 'int')}}
80 }
81
Issue55702(void)82 void Issue55702(void) {
83 // A controlling expression which uses __auto_type should not be
84 // automatically compatible with every association; we should be using the
85 // canonical type for that comparison.
86 void *ptr = 0;
87 __auto_type v = ptr;
88 (void)_Generic(v, long double : 0, double : 0, default : 1); // OK
89 _Static_assert(_Generic(v, long double : 0, default : 1) == 1, "fail");
90 }
91