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// RUN: %clang_cc1 -fexceptions -fsyntax-only -verify -std=c++0x -ffreestanding %s
#include <stdint.h>
typedef decltype(nullptr) nullptr_t;
struct A {};
int o1(char*);
void o1(uintptr_t);
void o2(char*); // expected-note {{candidate}}
void o2(int A::*); // expected-note {{candidate}}
nullptr_t f(nullptr_t null)
{
// Implicit conversions.
null = nullptr;
void *p = nullptr;
p = null;
int *pi = nullptr;
pi = null;
null = 0;
int A::*pm = nullptr;
pm = null;
void (*pf)() = nullptr;
pf = null;
void (A::*pmf)() = nullptr;
pmf = null;
bool b = nullptr;
// Can't convert nullptr to integral implicitly.
uintptr_t i = nullptr; // expected-error {{cannot initialize}}
// Operators
(void)(null == nullptr);
(void)(null <= nullptr);
(void)(null == (void*)0);
(void)((void*)0 == nullptr);
(void)(null <= (void*)0);
(void)((void*)0 <= nullptr);
(void)(0 == nullptr);
(void)(nullptr == 0);
(void)(nullptr <= 0);
(void)(0 <= nullptr);
(void)(1 > nullptr); // expected-error {{invalid operands to binary expression}}
(void)(1 != nullptr); // expected-error {{invalid operands to binary expression}}
(void)(1 + nullptr); // expected-error {{invalid operands to binary expression}}
(void)(0 ? nullptr : 0); // expected-error {{non-pointer operand type 'int' incompatible with nullptr}}
(void)(0 ? nullptr : (void*)0);
(void)(0 ? nullptr : A()); // expected-error {{non-pointer operand type 'A' incompatible with nullptr}}
(void)(0 ? A() : nullptr); // expected-error {{non-pointer operand type 'A' incompatible with nullptr}}
// Overloading
int t = o1(nullptr);
t = o1(null);
o2(nullptr); // expected-error {{ambiguous}}
// nullptr is an rvalue, null is an lvalue
(void)&nullptr; // expected-error {{address expression must be an lvalue}}
nullptr_t *pn = &null;
// You can reinterpret_cast nullptr to an integer.
(void)reinterpret_cast<uintptr_t>(nullptr);
// You can throw nullptr.
throw nullptr;
}
// Template arguments can be nullptr.
template <int *PI, void (*PF)(), int A::*PM, void (A::*PMF)()>
struct T {};
typedef T<nullptr, nullptr, nullptr, nullptr> NT;
namespace test1 {
template<typename T, typename U> struct is_same {
static const bool value = false;
};
template<typename T> struct is_same<T, T> {
static const bool value = true;
};
void *g(void*);
bool g(bool);
// Test that we prefer g(void*) over g(bool).
static_assert(is_same<decltype(g(nullptr)), void*>::value, "");
}
namespace test2 {
void f(int, ...) __attribute__((sentinel));
void g() {
// nullptr can be used as the sentinel value.
f(10, nullptr);
}
}
namespace test3 {
void f(const char*, ...) __attribute__((format(printf, 1, 2)));
void g() {
// Don't warn when using nullptr with %p.
f("%p", nullptr);
}
}
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