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| // RUN: %clang_cc1 -fcxx-exceptions -fexceptions -fsyntax-only -verify -std=c++11 -ffreestanding -Wno-null-conversion -Wno-tautological-compare %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); // expected-error {{invalid operands to binary expression}}
(void)(null == 0);
(void)(null == (void*)0);
(void)((void*)0 == nullptr);
(void)(null <= 0); // expected-error {{invalid operands to binary expression}}
(void)(null <= (void*)0); // expected-error {{invalid operands to binary expression}}
(void)((void*)0 <= nullptr); // expected-error {{invalid operands to binary expression}}
(void)(0 == nullptr);
(void)(nullptr == 0);
(void)(nullptr <= 0); // expected-error {{invalid operands to binary expression}}
(void)(0 <= 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)(1 + nullptr); // expected-error {{invalid operands to binary expression}}
(void)(0 ? nullptr : 0);
(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 {{cannot take the address of an rvalue of type 'nullptr_t'}}
nullptr_t *pn = &null;
// You can reinterpret_cast nullptr to an integer.
(void)reinterpret_cast<uintptr_t>(nullptr);
(void)reinterpret_cast<uintptr_t>(*pn);
// You can't reinterpret_cast nullptr to any integer
(void)reinterpret_cast<char>(nullptr); // expected-error {{cast from pointer to smaller type 'char' loses information}}
int *ip = *pn;
if (*pn) { }
// 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);
}
}
static_assert(__is_scalar(nullptr_t), "");
static_assert(__is_pod(nullptr_t), "");
static_assert(sizeof(nullptr_t) == sizeof(void*), "");
static_assert(!(nullptr < nullptr), ""); // expected-error {{invalid operands to binary expression}}
static_assert(!(nullptr > nullptr), ""); // expected-error {{invalid operands to binary expression}}
static_assert( nullptr <= nullptr, ""); // expected-error {{invalid operands to binary expression}}
static_assert( nullptr >= nullptr, ""); // expected-error {{invalid operands to binary expression}}
static_assert( nullptr == nullptr, "");
static_assert(!(nullptr != nullptr), "");
static_assert(!(0 < nullptr), ""); // expected-error {{invalid operands to binary expression}}
static_assert(!(0 > nullptr), ""); // expected-error {{invalid operands to binary expression}}
static_assert( 0 <= nullptr, ""); // expected-error {{invalid operands to binary expression}}
static_assert( 0 >= nullptr, ""); // expected-error {{invalid operands to binary expression}}
static_assert( 0 == nullptr, "");
static_assert(!(0 != nullptr), "");
static_assert(!(nullptr < 0), ""); // expected-error {{invalid operands to binary expression}}
static_assert(!(nullptr > 0), ""); // expected-error {{invalid operands to binary expression}}
static_assert( nullptr <= 0, ""); // expected-error {{invalid operands to binary expression}}
static_assert( nullptr >= 0, ""); // expected-error {{invalid operands to binary expression}}
static_assert( nullptr == 0, "");
static_assert(!(nullptr != 0), "");
namespace overloading {
int &f1(int*);
float &f1(bool);
void test_f1() {
int &ir = (f1)(nullptr);
}
struct ConvertsToNullPtr {
operator nullptr_t() const;
};
void test_conversion(ConvertsToNullPtr ctn) {
(void)(ctn == ctn);
(void)(ctn != ctn);
(void)(ctn <= ctn); // expected-error {{invalid operands to binary expression}}
(void)(ctn >= ctn); // expected-error {{invalid operands to binary expression}}
(void)(ctn < ctn); // expected-error {{invalid operands to binary expression}}
(void)(ctn > ctn); // expected-error {{invalid operands to binary expression}}
}
}
namespace templates {
template<typename T, nullptr_t Value>
struct X {
X() { ptr = Value; }
T *ptr;
};
X<int, nullptr> x;
template<int (*fp)(int), int* p, int A::* pmd, int (A::*pmf)(int)>
struct X2 {};
X2<nullptr, nullptr, nullptr, nullptr> x2;
}
namespace null_pointer_constant {
// Pending implementation of core issue 903, ensure we don't allow any of the
// C++11 constant evaluation semantics in null pointer constants.
struct S { int n; };
constexpr int null() { return 0; }
void *p = S().n; // expected-error {{cannot initialize}}
void *q = null(); // expected-error {{cannot initialize}}
}
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