1 // RUN: %clang_cc1 -fcxx-exceptions -fexceptions -fsyntax-only -verify -std=c++11 -Wsign-conversion %s
2 
3 // C++ rules for ?: are a lot stricter than C rules, and have to take into
4 // account more conversion options.
5 // This test runs in C++11 mode for the contextual conversion of the condition.
6 
7 struct ToBool { explicit operator bool(); };
8 
9 struct B;
10 struct A {
11   A();
12   A(const B&); // expected-note 2 {{candidate constructor}}
13 };
14 struct B { operator A() const; }; // expected-note 2 {{candidate function}}
15 struct I { operator int(); };
16 struct J { operator I(); };
17 struct K { operator double(); };
18 typedef void (*vfn)();
19 struct F { operator vfn(); };
20 struct G { operator vfn(); };
21 
22 struct Base {
23   int trick();
24   A trick() const;
25   void fn1();
26 };
27 struct Derived : Base {
28   void fn2();
29 };
30 struct Convertible { operator Base&(); };
31 struct Priv : private Base {}; // expected-note 4 {{declared private here}}
32 struct Mid : Base {};
33 struct Fin : Mid, Derived {};
34 typedef void (Derived::*DFnPtr)();
35 struct ToMemPtr { operator DFnPtr(); };
36 
37 struct BadDerived;
38 struct BadBase { operator BadDerived&(); };
39 struct BadDerived : BadBase {};
40 
41 struct Fields {
42   int i1, i2, b1 : 3, b2 : 3;
43 };
44 struct MixedFields {
45   int i;
46   volatile int vi;
47   const int ci;
48   const volatile int cvi;
49 };
50 struct MixedFieldsDerived : MixedFields {
51 };
52 
53 enum Enum { EVal };
54 
55 struct Ambig {
56   operator short(); // expected-note 2 {{candidate function}}
57   operator signed char(); // expected-note 2 {{candidate function}}
58 };
59 
60 struct Abstract {
61   virtual ~Abstract() = 0; // expected-note {{unimplemented pure virtual method '~Abstract' in 'Abstract'}}
62 };
63 
64 struct Derived1: Abstract {
65 };
66 
67 struct Derived2: Abstract {
68 };
69 
70 void test()
71 {
72   // This function tests C++0x 5.16
73 
74   // p1 (contextually convert to bool)
75   int i1 = ToBool() ? 0 : 1;
76 
77   // p2 (one or both void, and throwing)
78   i1 ? throw 0 : throw 1;
79   i1 ? test() : throw 1;
80   i1 ? throw 0 : test();
81   i1 ? test() : test();
82   i1 = i1 ? throw 0 : 0;
83   i1 = i1 ? 0 : throw 0;
84   i1 = i1 ? (throw 0) : 0;
85   i1 = i1 ? 0 : (throw 0);
86   i1 ? 0 : test(); // expected-error {{right operand to ? is void, but left operand is of type 'int'}}
87   i1 ? test() : 0; // expected-error {{left operand to ? is void, but right operand is of type 'int'}}
88   (i1 ? throw 0 : i1) = 0; // expected-error {{expression is not assignable}}
89   (i1 ? i1 : throw 0) = 0; // expected-error {{expression is not assignable}}
90 
91   // p3 (one or both class type, convert to each other)
92   // b1 (lvalues)
93   Base base;
94   Derived derived;
95   Convertible conv;
96   Base &bar1 = i1 ? base : derived;
97   Base &bar2 = i1 ? derived : base;
98   Base &bar3 = i1 ? base : conv;
99   Base &bar4 = i1 ? conv : base;
100   // these are ambiguous
101   BadBase bb;
102   BadDerived bd;
103   (void)(i1 ? bb : bd); // expected-error {{conditional expression is ambiguous; 'BadBase' can be converted to 'BadDerived' and vice versa}}
104   (void)(i1 ? bd : bb); // expected-error {{conditional expression is ambiguous}}
105   // curiously enough (and a defect?), these are not
106   // for rvalues, hierarchy takes precedence over other conversions
107   (void)(i1 ? BadBase() : BadDerived());
108   (void)(i1 ? BadDerived() : BadBase());
109 
110   // b2.1 (hierarchy stuff)
111   extern const Base constret();
112   extern const Derived constder();
113   // should use const overload
114   A a1((i1 ? constret() : Base()).trick());
115   A a2((i1 ? Base() : constret()).trick());
116   A a3((i1 ? constret() : Derived()).trick());
117   A a4((i1 ? Derived() : constret()).trick());
118   // should use non-const overload
119   i1 = (i1 ? Base() : Base()).trick();
120   i1 = (i1 ? Base() : Base()).trick();
121   i1 = (i1 ? Base() : Derived()).trick();
122   i1 = (i1 ? Derived() : Base()).trick();
123   // should fail: const lost
124   (void)(i1 ? Base() : constder()); // expected-error {{incompatible operand types ('Base' and 'const Derived')}}
125   (void)(i1 ? constder() : Base()); // expected-error {{incompatible operand types ('const Derived' and 'Base')}}
126 
127   Priv priv;
128   Fin fin;
129   (void)(i1 ? Base() : Priv()); // expected-error{{private base class}}
130   (void)(i1 ? Priv() : Base()); // expected-error{{private base class}}
131   (void)(i1 ? Base() : Fin()); // expected-error{{ambiguous conversion from derived class 'Fin' to base class 'Base':}}
132   (void)(i1 ? Fin() : Base()); // expected-error{{ambiguous conversion from derived class 'Fin' to base class 'Base':}}
133   (void)(i1 ? base : priv); // expected-error {{private base class}}
134   (void)(i1 ? priv : base); // expected-error {{private base class}}
135   (void)(i1 ? base : fin); // expected-error {{ambiguous conversion from derived class 'Fin' to base class 'Base':}}
136   (void)(i1 ? fin : base); // expected-error {{ambiguous conversion from derived class 'Fin' to base class 'Base':}}
137 
138   // b2.2 (non-hierarchy)
139   i1 = i1 ? I() : i1;
140   i1 = i1 ? i1 : I();
141   I i2(i1 ? I() : J());
142   I i3(i1 ? J() : I());
143   // "the type [it] woud have if E2 were converted to an rvalue"
144   vfn pfn = i1 ? F() : test;
145   pfn = i1 ? test : F();
146   (void)(i1 ? A() : B()); // expected-error {{conversion from 'B' to 'A' is ambiguous}}
147   (void)(i1 ? B() : A()); // expected-error {{conversion from 'B' to 'A' is ambiguous}}
148   (void)(i1 ? 1 : Ambig()); // expected-error {{conversion from 'Ambig' to 'int' is ambiguous}}
149   (void)(i1 ? Ambig() : 1); // expected-error {{conversion from 'Ambig' to 'int' is ambiguous}}
150   // By the way, this isn't an lvalue:
151   &(i1 ? i1 : i2); // expected-error {{cannot take the address of an rvalue}}
152 
153   // p4 (lvalue, same type)
154   Fields flds;
155   int &ir1 = i1 ? flds.i1 : flds.i2;
156   (i1 ? flds.b1 : flds.i2) = 0;
157   (i1 ? flds.i1 : flds.b2) = 0;
158   (i1 ? flds.b1 : flds.b2) = 0;
159 
160   // p5 (conversion to built-in types)
161   // GCC 4.3 fails these
162   double d1 = i1 ? I() : K();
163   pfn = i1 ? F() : G();
164   DFnPtr pfm;
165   pfm = i1 ? DFnPtr() : &Base::fn1;
166   pfm = i1 ? &Base::fn1 : DFnPtr();
167 
168   // p6 (final conversions)
169   i1 = i1 ? i1 : ir1;
170   int *pi1 = i1 ? &i1 : 0;
171   pi1 = i1 ? 0 : &i1;
172   i1 = i1 ? i1 : EVal;
173   i1 = i1 ? EVal : i1;
174   d1 = i1 ? 'c' : 4.0;
175   d1 = i1 ? 4.0 : 'c';
176   Base *pb = i1 ? (Base*)0 : (Derived*)0;
177   pb = i1 ? (Derived*)0 : (Base*)0;
178   pfm = i1 ? &Base::fn1 : &Derived::fn2;
179   pfm = i1 ? &Derived::fn2 : &Base::fn1;
180   pfm = i1 ? &Derived::fn2 : 0;
181   pfm = i1 ? 0 : &Derived::fn2;
182   const int (MixedFieldsDerived::*mp1) =
183     i1 ? &MixedFields::ci : &MixedFieldsDerived::i;
184   const volatile int (MixedFields::*mp2) =
185     i1 ? &MixedFields::ci : &MixedFields::cvi;
186   (void)(i1 ? &MixedFields::ci : &MixedFields::vi);
187   // Conversion of primitives does not result in an lvalue.
188   &(i1 ? i1 : d1); // expected-error {{cannot take the address of an rvalue}}
189 
190   (void)&(i1 ? flds.b1 : flds.i1); // expected-error {{address of bit-field requested}}
191   (void)&(i1 ? flds.i1 : flds.b1); // expected-error {{address of bit-field requested}}
192 
193 
194   unsigned long test0 = 5;
195   test0 = test0 ? (long) test0 : test0; // expected-warning {{operand of ? changes signedness: 'long' to 'unsigned long'}}
196   test0 = test0 ? (int) test0 : test0; // expected-warning {{operand of ? changes signedness: 'int' to 'unsigned long'}}
197   test0 = test0 ? (short) test0 : test0; // expected-warning {{operand of ? changes signedness: 'short' to 'unsigned long'}}
198   test0 = test0 ? test0 : (long) test0; // expected-warning {{operand of ? changes signedness: 'long' to 'unsigned long'}}
199   test0 = test0 ? test0 : (int) test0; // expected-warning {{operand of ? changes signedness: 'int' to 'unsigned long'}}
200   test0 = test0 ? test0 : (short) test0; // expected-warning {{operand of ? changes signedness: 'short' to 'unsigned long'}}
201   test0 = test0 ? test0 : (long) 10;
202   test0 = test0 ? test0 : (int) 10;
203   test0 = test0 ? test0 : (short) 10;
204   test0 = test0 ? (long) 10 : test0;
205   test0 = test0 ? (int) 10 : test0;
206   test0 = test0 ? (short) 10 : test0;
207 
208   int test1;
209   test0 = test0 ? EVal : test0;
210   test1 = test0 ? EVal : (int) test0;
211 
212   test0 = test0 ? EVal : test1; // expected-warning {{operand of ? changes signedness: 'int' to 'unsigned long'}}
213   test0 = test0 ? test1 : EVal; // expected-warning {{operand of ? changes signedness: 'int' to 'unsigned long'}}
214 
215   test1 = test0 ? EVal : (int) test0;
216   test1 = test0 ? (int) test0 : EVal;
217 
218   // Note the thing that this does not test: since DR446, various situations
219   // *must* create a separate temporary copy of class objects. This can only
220   // be properly tested at runtime, though.
221 
222   const Abstract &a = true ? static_cast<const Abstract&>(Derived1()) : Derived2(); // expected-error {{allocating an object of abstract class type 'const Abstract'}}
223   true ? static_cast<const Abstract&>(Derived1()) : throw 3; // expected-error {{allocating an object of abstract class type 'const Abstract'}}
224 }
225 
226 namespace PR6595 {
227   struct OtherString {
228     OtherString();
229     OtherString(const char*);
230   };
231 
232   struct String {
233     String(const char *);
234     String(const OtherString&);
235     operator const char*() const;
236   };
237 
238   void f(bool Cond, String S, OtherString OS) {
239     (void)(Cond? S : "");
240     (void)(Cond? "" : S);
241     const char a[1] = {'a'};
242     (void)(Cond? S : a);
243     (void)(Cond? a : S);
244     (void)(Cond? OS : S);
245   }
246 }
247 
248 namespace PR6757 {
249   struct Foo1 {
250     Foo1();
251     Foo1(const Foo1&);
252   };
253 
254   struct Foo2 { };
255 
256   struct Foo3 {
257     Foo3();
258     Foo3(Foo3&); // expected-note{{would lose const qualifier}}
259   };
260 
261   struct Bar {
262     operator const Foo1&() const;
263     operator const Foo2&() const;
264     operator const Foo3&() const;
265   };
266 
267   void f() {
268     (void)(true ? Bar() : Foo1()); // okay
269     (void)(true ? Bar() : Foo2()); // okay
270     (void)(true ? Bar() : Foo3()); // expected-error{{no viable constructor copying temporary}}
271   }
272 }
273 
274 // Reduced from selfhost.
275 namespace test1 {
276   struct A {
277     enum Foo {
278       fa, fb, fc, fd, fe, ff
279     };
280 
281     Foo x();
282   };
283 
284   void foo(int);
285 
286   void test(A *a) {
287     foo(a ? a->x() : 0);
288   }
289 }
290 
291 namespace rdar7998817 {
292   class X {
293     X(X&); // expected-note{{declared private here}}
294 
295     struct ref { };
296 
297   public:
298     X();
299     X(ref);
300 
301     operator ref();
302   };
303 
304   void f(bool B) {
305     X x;
306     (void)(B? x // expected-error{{calling a private constructor of class 'rdar7998817::X'}}
307            : X());
308   }
309 }
310 
311 namespace PR7598 {
312   enum Enum {
313     v = 1,
314   };
315 
316   const Enum g() {
317     return v;
318   }
319 
320   const volatile Enum g2() {
321     return v;
322   }
323 
324   void f() {
325     const Enum v2 = v;
326     Enum e = false ? g() : v;
327     Enum e2 = false ? v2 : v;
328     Enum e3 = false ? g2() : v;
329   }
330 
331 }
332 
333 namespace PR9236 {
334 #define NULL 0L
335   void f() {
336     int i;
337     (void)(true ? A() : NULL); // expected-error{{non-pointer operand type 'A' incompatible with NULL}}
338     (void)(true ? NULL : A()); // expected-error{{non-pointer operand type 'A' incompatible with NULL}}
339     (void)(true ? 0 : A()); // expected-error{{incompatible operand types}}
340     (void)(true ? nullptr : A()); // expected-error{{non-pointer operand type 'A' incompatible with nullptr}}
341     (void)(true ? nullptr : i); // expected-error{{non-pointer operand type 'int' incompatible with nullptr}}
342     (void)(true ? __null : A()); // expected-error{{non-pointer operand type 'A' incompatible with NULL}}
343     (void)(true ? (void*)0 : A()); // expected-error{{incompatible operand types}}
344   }
345 }
346 
347 namespace DR587 {
348   template<typename T>
349   const T *f(bool b) {
350     static T t1 = T();
351     static const T t2 = T();
352     return &(b ? t1 : t2);
353   }
354   struct S {};
355   template const int *f(bool);
356   template const S *f(bool);
357 
358   extern bool b;
359   int i = 0;
360   const int ci = 0;
361   volatile int vi = 0;
362   const volatile int cvi = 0;
363 
364   const int &cir = b ? i : ci;
365   volatile int &vir = b ? vi : i;
366   const volatile int &cvir1 = b ? ci : cvi;
367   const volatile int &cvir2 = b ? cvi : vi;
368   const volatile int &cvir3 = b ? ci : vi; // expected-error{{volatile lvalue reference to type 'const volatile int' cannot bind to a temporary of type 'int'}}
369 }
370