1 // RUN: %clang_cc1 -fsyntax-only -verify %s 2 int g(int); 3 4 void f() { 5 int i; 6 int &r = i; 7 r = 1; 8 int *p = &r; 9 int &rr = r; 10 int (&rg)(int) = g; 11 rg(i); 12 int a[3]; 13 int (&ra)[3] = a; 14 ra[1] = i; 15 int *Q; 16 int *& P = Q; 17 P[1] = 1; 18 } 19 20 typedef int t[1]; 21 void test2() { 22 t a; 23 t& b = a; 24 25 26 int c[3]; 27 int (&rc)[3] = c; 28 } 29 30 // C++ [dcl.init.ref]p5b1 31 struct A { }; 32 struct B : A { } b; 33 34 void test3() { 35 double d = 2.0; 36 double& rd = d; // rd refers to d 37 const double& rcd = d; // rcd refers to d 38 39 A& ra = b; // ra refers to A subobject in b 40 const A& rca = b; // rca refers to A subobject in b 41 } 42 43 B fB(); 44 45 // C++ [dcl.init.ref]p5b2 46 void test4() { 47 double& rd2 = 2.0; // expected-error{{non-const lvalue reference to type 'double' cannot bind to a temporary of type 'double'}} 48 int i = 2; 49 double& rd3 = i; // expected-error{{non-const lvalue reference to type 'double' cannot bind to a value of unrelated type 'int'}} 50 51 const A& rca = fB(); 52 } 53 54 void test5() { 55 // const double& rcd2 = 2; // rcd2 refers to temporary with value 2.0 56 const volatile int cvi = 1; 57 const int& r = cvi; // expected-error{{binding of reference to type 'const int' to a value of type 'const volatile int' drops qualifiers}} 58 } 59 60 // C++ [dcl.init.ref]p3 61 int& test6(int& x) { 62 int& yo; // expected-error{{declaration of reference variable 'yo' requires an initializer}} 63 64 return x; 65 } 66 int& not_initialized_error; // expected-error{{declaration of reference variable 'not_initialized_error' requires an initializer}} 67 extern int& not_initialized_okay; 68 69 class Test6 { // expected-warning{{class 'Test6' does not declare any constructor to initialize its non-modifiable members}} 70 int& okay; // expected-note{{reference member 'okay' will never be initialized}} 71 }; 72 73 struct C : B, A { }; 74 75 void test7(C& c) { 76 A& a1 = c; // expected-error {{ambiguous conversion from derived class 'C' to base class 'A':}} 77 } 78 79 // C++ [dcl.ref]p1, C++ [dcl.ref]p4 80 void test8(int& const,// expected-error{{'const' qualifier may not be applied to a reference}} 81 82 void&, // expected-error{{cannot form a reference to 'void'}} 83 int& &) // expected-error{{type name declared as a reference to a reference}} 84 { 85 typedef int& intref; 86 typedef intref& intrefref; // C++ DR 106: reference collapsing 87 88 typedef intref const intref_c; // okay. FIXME: how do we verify that this is the same type as intref? 89 } 90 91 92 class string { 93 char *Data; 94 unsigned Length; 95 public: 96 string(); 97 ~string(); 98 }; 99 100 string getInput(); 101 102 void test9() { 103 string &s = getInput(); // expected-error{{lvalue reference}} 104 } 105 106 void test10() { 107 __attribute((vector_size(16))) typedef int vec4; 108 typedef __attribute__(( ext_vector_type(4) )) int ext_vec4; 109 110 vec4 v; 111 int &a = v[0]; // expected-error{{non-const reference cannot bind to vector element}} 112 const int &b = v[0]; 113 114 ext_vec4 ev; 115 int &c = ev.x; // expected-error{{non-const reference cannot bind to vector element}} 116 const int &d = ev.x; 117 } 118 119 namespace PR7149 { 120 template<typename T> struct X0 121 { 122 T& first; 123 X0(T& p1) : first(p1) { } 124 }; 125 126 127 void f() 128 { 129 int p1[1]; 130 X0< const int[1]> c(p1); 131 } 132 } 133 134 namespace PR8608 { 135 bool& f(unsigned char& c) { return (bool&)c; } 136 } 137 138 // The following crashed trying to recursively evaluate the LValue. 139 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}} 140 141 namespace ExplicitRefInit { 142 // This is invalid: we can't copy-initialize an 'A' temporary using an 143 // explicit constructor. 144 struct A { explicit A(int); }; 145 const A &a(0); // expected-error {{reference to type 'const ExplicitRefInit::A' could not bind to an rvalue of type 'int'}} 146 } 147