1 // RUN: %clang_cc1 -fcxx-exceptions -fexceptions -fsyntax-only -verify -std=c++11 -ffreestanding %s
2 #include <stdint.h>
3
4 typedef decltype(nullptr) nullptr_t;
5
6 struct A {};
7
8 int o1(char*);
9 void o1(uintptr_t);
10 void o2(char*); // expected-note {{candidate}}
11 void o2(int A::*); // expected-note {{candidate}}
12
f(nullptr_t null)13 nullptr_t f(nullptr_t null)
14 {
15 // Implicit conversions.
16 null = nullptr;
17 void *p = nullptr;
18 p = null;
19 int *pi = nullptr;
20 pi = null;
21 null = 0;
22 int A::*pm = nullptr;
23 pm = null;
24 void (*pf)() = nullptr;
25 pf = null;
26 void (A::*pmf)() = nullptr;
27 pmf = null;
28 bool b = nullptr;
29
30 // Can't convert nullptr to integral implicitly.
31 uintptr_t i = nullptr; // expected-error {{cannot initialize}}
32
33 // Operators
34 (void)(null == nullptr);
35 (void)(null <= nullptr);
36 (void)(null == 0);
37 (void)(null == (void*)0);
38 (void)((void*)0 == nullptr);
39 (void)(null <= 0);
40 (void)(null <= (void*)0);
41 (void)((void*)0 <= nullptr);
42 (void)(0 == nullptr);
43 (void)(nullptr == 0);
44 (void)(nullptr <= 0);
45 (void)(0 <= nullptr);
46 (void)(1 > nullptr); // expected-error {{invalid operands to binary expression}}
47 (void)(1 != nullptr); // expected-error {{invalid operands to binary expression}}
48 (void)(1 + nullptr); // expected-error {{invalid operands to binary expression}}
49 (void)(0 ? nullptr : 0);
50 (void)(0 ? nullptr : (void*)0);
51 (void)(0 ? nullptr : A()); // expected-error {{non-pointer operand type 'A' incompatible with nullptr}}
52 (void)(0 ? A() : nullptr); // expected-error {{non-pointer operand type 'A' incompatible with nullptr}}
53
54 // Overloading
55 int t = o1(nullptr);
56 t = o1(null);
57 o2(nullptr); // expected-error {{ambiguous}}
58
59 // nullptr is an rvalue, null is an lvalue
60 (void)&nullptr; // expected-error {{cannot take the address of an rvalue of type 'nullptr_t'}}
61 nullptr_t *pn = &null;
62
63 // You can reinterpret_cast nullptr to an integer.
64 (void)reinterpret_cast<uintptr_t>(nullptr);
65 (void)reinterpret_cast<uintptr_t>(*pn);
66
67 int *ip = *pn;
68 if (*pn) { }
69
70 // You can throw nullptr.
71 throw nullptr;
72 }
73
74 // Template arguments can be nullptr.
75 template <int *PI, void (*PF)(), int A::*PM, void (A::*PMF)()>
76 struct T {};
77
78 typedef T<nullptr, nullptr, nullptr, nullptr> NT;
79
80 namespace test1 {
81 template<typename T, typename U> struct is_same {
82 static const bool value = false;
83 };
84
85 template<typename T> struct is_same<T, T> {
86 static const bool value = true;
87 };
88
89 void *g(void*);
90 bool g(bool);
91
92 // Test that we prefer g(void*) over g(bool).
93 static_assert(is_same<decltype(g(nullptr)), void*>::value, "");
94 }
95
96 namespace test2 {
97 void f(int, ...) __attribute__((sentinel));
98
g()99 void g() {
100 // nullptr can be used as the sentinel value.
101 f(10, nullptr);
102 }
103 }
104
105 namespace test3 {
106 void f(const char*, ...) __attribute__((format(printf, 1, 2)));
107
g()108 void g() {
109 // Don't warn when using nullptr with %p.
110 f("%p", nullptr);
111 }
112 }
113
114 static_assert(__is_scalar(nullptr_t), "");
115 static_assert(__is_pod(nullptr_t), "");
116 static_assert(sizeof(nullptr_t) == sizeof(void*), "");
117
118 static_assert(!(nullptr < nullptr), "");
119 static_assert(!(nullptr > nullptr), "");
120 static_assert( nullptr <= nullptr, "");
121 static_assert( nullptr >= nullptr, "");
122 static_assert( nullptr == nullptr, "");
123 static_assert(!(nullptr != nullptr), "");
124
125 static_assert(!(0 < nullptr), "");
126 static_assert(!(0 > nullptr), "");
127 static_assert( 0 <= nullptr, "");
128 static_assert( 0 >= nullptr, "");
129 static_assert( 0 == nullptr, "");
130 static_assert(!(0 != nullptr), "");
131
132 static_assert(!(nullptr < 0), "");
133 static_assert(!(nullptr > 0), "");
134 static_assert( nullptr <= 0, "");
135 static_assert( nullptr >= 0, "");
136 static_assert( nullptr == 0, "");
137 static_assert(!(nullptr != 0), "");
138
139 namespace overloading {
140 int &f1(int*);
141 float &f1(bool);
142
test_f1()143 void test_f1() {
144 int &ir = (f1)(nullptr);
145 }
146
147 struct ConvertsToNullPtr {
148 operator nullptr_t() const;
149 };
150
test_conversion(ConvertsToNullPtr ctn)151 void test_conversion(ConvertsToNullPtr ctn) {
152 (void)(ctn == ctn);
153 (void)(ctn != ctn);
154 (void)(ctn <= ctn);
155 (void)(ctn >= ctn);
156 (void)(ctn < ctn);
157 (void)(ctn > ctn);
158 }
159 }
160
161 namespace templates {
162 template<typename T, nullptr_t Value>
163 struct X {
Xtemplates::X164 X() { ptr = Value; }
165
166 T *ptr;
167 };
168
169 X<int, nullptr> x;
170
171
172 template<int (*fp)(int), int* p, int A::* pmd, int (A::*pmf)(int)>
173 struct X2 {};
174
175 X2<nullptr, nullptr, nullptr, nullptr> x2;
176 }
177
178 namespace null_pointer_constant {
179
180 // Pending implementation of core issue 903, ensure we don't allow any of the
181 // C++11 constant evaluation semantics in null pointer constants.
182 struct S { int n; };
null()183 constexpr int null() { return 0; }
184 void *p = S().n; // expected-error {{cannot initialize}}
185 void *q = null(); // expected-error {{cannot initialize}}
186
187 }
188