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// RUN: %clang_cc1 -fsyntax-only -verify %s
// RUN: %clang_cc1 -std=c++11 -fsyntax-only -verify %s
// RUN: %clang_cc1 -std=c++14 -fsyntax-only -verify %s
int g(int);
void f() {
int i;
int &r = i;
r = 1;
int *p = &r;
int &rr = r;
int (&rg)(int) = g;
rg(i);
int a[3];
int (&ra)[3] = a;
ra[1] = i;
int *Q;
int *& P = Q;
P[1] = 1;
}
typedef int t[1];
void test2() {
t a;
t& b = a;
int c[3];
int (&rc)[3] = c;
}
// C++ [dcl.init.ref]p5b1
struct A { };
struct B : A { } b;
void test3() {
double d = 2.0;
double& rd = d; // rd refers to d
const double& rcd = d; // rcd refers to d
A& ra = b; // ra refers to A subobject in b
const A& rca = b; // rca refers to A subobject in b
}
B fB();
// C++ [dcl.init.ref]p5b2
void test4() {
double& rd2 = 2.0; // expected-error{{non-const lvalue reference to type 'double' cannot bind to a temporary of type 'double'}}
int i = 2;
double& rd3 = i; // expected-error{{non-const lvalue reference to type 'double' cannot bind to a value of unrelated type 'int'}}
const A& rca = fB();
}
void test5() {
// const double& rcd2 = 2; // rcd2 refers to temporary with value 2.0
const volatile int cvi = 1;
const int& r = cvi; // expected-error{{binding reference of type 'const int' to value of type 'const volatile int' drops 'volatile' qualifier}}
#if __cplusplus >= 201103L
const int& r2{cvi}; // expected-error{{binding reference of type 'const int' to value of type 'const volatile int' drops 'volatile' qualifier}}
const int a = 2;
int& r3{a}; // expected-error{{binding reference of type 'int' to value of type 'const int' drops 'const' qualifier}}
const int&& r4{a}; // expected-error{{rvalue reference to type 'const int' cannot bind to lvalue of type 'const int'}}
void func();
void func(int);
int &ptr1 = {func}; // expected-error{{address of overloaded function 'func' does not match required type 'int'}}
int &&ptr2{func}; // expected-error{{address of overloaded function 'func' does not match required type 'int'}}
// expected-note@-4{{candidate function}}
// expected-note@-4{{candidate function}}
// expected-note@-6{{candidate function}}
// expected-note@-6{{candidate function}}
#endif
}
// C++ [dcl.init.ref]p3
int& test6(int& x) {
int& yo; // expected-error{{declaration of reference variable 'yo' requires an initializer}}
return x;
}
int& not_initialized_error; // expected-error{{declaration of reference variable 'not_initialized_error' requires an initializer}}
extern int& not_initialized_okay;
class Test6 { // expected-warning{{class 'Test6' does not declare any constructor to initialize its non-modifiable members}}
int& okay; // expected-note{{reference member 'okay' will never be initialized}}
};
struct C : B, A { }; // expected-warning {{direct base 'A' is inaccessible due to ambiguity:\n struct C -> struct B -> struct A\nstruct C -> struct A}}
void test7(C& c) {
A& a1 = c; // expected-error {{ambiguous conversion from derived class 'C' to base class 'A':}}
}
// C++ [dcl.ref]p1, C++ [dcl.ref]p4
void test8(int& const,// expected-error{{'const' qualifier may not be applied to a reference}}
void&, // expected-error{{cannot form a reference to 'void'}}
int& &) // expected-error{{type name declared as a reference to a reference}}
{
typedef int& intref;
typedef intref& intrefref; // C++ DR 106: reference collapsing
typedef intref const intref_c; // expected-warning {{'const' qualifier on reference type 'intref' (aka 'int &') has no effect}}
typedef intref_c intref; // ok, same type
typedef intref volatile intref; // expected-warning {{'volatile' qualifier on reference type 'intref' (aka 'int &') has no effect}}
typedef intref _Atomic intref; // expected-warning {{'_Atomic' qualifier on reference type 'intref' (aka 'int &') has no effect}}
void restrict_ref(__restrict intref); // ok
void restrict_ref(int &__restrict); // ok
}
namespace var_template {
#if __cplusplus >= 201402L
int i;
template <typename> int &ref = i; // ok
template <> int &ref<float>; // expected-error {{declaration of reference variable 'ref<float>' requires an initializer}}
#endif
} // namespace var_template
template<typename T> int const_param(const T) {}
int const_ref_param = const_param<int&>(const_ref_param); // no-warning
class string {
char *Data;
unsigned Length;
public:
string();
~string();
};
string getInput();
void test9() {
string &s = getInput(); // expected-error{{lvalue reference}}
}
void test10() {
__attribute((vector_size(16))) typedef int vec4;
typedef __attribute__(( ext_vector_type(4) )) int ext_vec4;
vec4 v;
int &a = v[0]; // expected-error{{non-const reference cannot bind to vector element}}
const int &b = v[0];
ext_vec4 ev;
int &c = ev.x; // expected-error{{non-const reference cannot bind to vector element}}
const int &d = ev.x;
}
namespace PR7149 {
template<typename T> struct X0
{
T& first;
X0(T& p1) : first(p1) { }
};
void f()
{
int p1[1];
X0< const int[1]> c(p1);
}
}
namespace PR8608 {
bool& f(unsigned char& c) { return (bool&)c; }
}
// The following crashed trying to recursively evaluate the LValue.
const int &do_not_crash = do_not_crash; // expected-warning{{reference 'do_not_crash' is not yet bound to a value when used within its own initialization}}
namespace ExplicitRefInit {
// This is invalid: we can't copy-initialize an 'A' temporary using an
// explicit constructor.
struct A { explicit A(int); };
const A &a(0); // expected-error {{reference to type 'const ExplicitRefInit::A' could not bind to an rvalue of type 'int'}}
}
namespace RefCollapseTypePrinting {
template<typename T> void add_lref() {
using X = int(T); // expected-note 4{{previous}}
using X = const volatile T&;
// expected-error@-1 {{'int &' vs 'int (int &)'}}
// expected-error@-2 {{'int &' vs 'int (int &&)'}}
// expected-error@-3 {{'const int &' vs 'int (const int &)'}}
// expected-error@-4 {{'const int &' vs 'int (const int &&)'}}
}
template void add_lref<int&>(); // expected-note {{instantiation of}}
template void add_lref<int&&>(); // expected-note {{instantiation of}}
template void add_lref<const int&>(); // expected-note {{instantiation of}}
template void add_lref<const int&&>(); // expected-note {{instantiation of}}
template<typename T> void add_rref() {
using X = int(T); // expected-note 4{{previous}}
using X = const volatile T&&;
// expected-error@-1 {{'int &' vs 'int (int &)'}}
// expected-error@-2 {{'int &&' vs 'int (int &&)'}}
// expected-error@-3 {{'const int &' vs 'int (const int &)'}}
// expected-error@-4 {{'const int &&' vs 'int (const int &&)'}}
}
template void add_rref<int&>(); // expected-note {{instantiation of}}
template void add_rref<int&&>(); // expected-note {{instantiation of}}
template void add_rref<const int&>(); // expected-note {{instantiation of}}
template void add_rref<const int&&>(); // expected-note {{instantiation of}}
}
namespace PR45521 {
struct a { template<class b> a(const b * const&); };
int *d;
const a &r = d;
}
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