conditional-expr.cpp revision 76458501a8963fa11b91c9337a487de6871169b4
13201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl// RUN: clang-cc -fsyntax-only -verify -std=c++0x %s 23201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl 33201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl// C++ rules for ?: are a lot stricter than C rules, and have to take into 43201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl// account more conversion options. 53201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl// This test runs in C++0x mode for the contextual conversion of the condition. 63201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl 73201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct ToBool { explicit operator bool(); }; 83201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl 93201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct B; 103201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct A { A(); A(const B&); }; 113201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct B { operator A() const; }; 123201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct I { operator int(); }; 133201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct J { operator I(); }; 143201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct K { operator double(); }; 153201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redltypedef void (*vfn)(); 163201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct F { operator vfn(); }; 173201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct G { operator vfn(); }; 183201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl 193201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct Base { 203201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl int trick(); 213201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl A trick() const; 2276458501a8963fa11b91c9337a487de6871169b4Sebastian Redl void fn1(); 2376458501a8963fa11b91c9337a487de6871169b4Sebastian Redl}; 2476458501a8963fa11b91c9337a487de6871169b4Sebastian Redlstruct Derived : Base { 2576458501a8963fa11b91c9337a487de6871169b4Sebastian Redl void fn2(); 263201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl}; 273201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct Convertible { operator Base&(); }; 283201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct Priv : private Base {}; 293201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct Mid : Base {}; 303201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct Fin : Mid, Derived {}; 3176458501a8963fa11b91c9337a487de6871169b4Sebastian Redltypedef void (Derived::*DFnPtr)(); 3276458501a8963fa11b91c9337a487de6871169b4Sebastian Redlstruct ToMemPtr { operator DFnPtr(); }; 333201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl 343201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct BadDerived; 353201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct BadBase { operator BadDerived&(); }; 363201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct BadDerived : BadBase {}; 373201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl 383201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct Fields { 393201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl int i1, i2, b1 : 3, b2 : 3; 403201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl}; 413201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl 423201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlenum Enum { EVal }; 433201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl 443201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlstruct Ambig { 453201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl operator short(); 463201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl operator signed char(); 473201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl}; 483201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl 493201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redlvoid test() 503201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl{ 513201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // This function tests C++0x 5.16 523201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl 533201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // p1 (contextually convert to bool) 543201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl int i1 = ToBool() ? 0 : 1; 553201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl 563201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // p2 (one or both void, and throwing) 573201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl i1 ? throw 0 : throw 1; 583201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl i1 ? test() : throw 1; 593201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl i1 ? throw 0 : test(); 603201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl i1 ? test() : test(); 613201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl i1 = i1 ? throw 0 : 0; 623201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl i1 = i1 ? 0 : throw 0; 633201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl i1 ? 0 : test(); // expected-error {{right operand to ? is void, but left operand is of type 'int'}} 643201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl i1 ? test() : 0; // expected-error {{left operand to ? is void, but right operand is of type 'int'}} 653201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl (i1 ? throw 0 : i1) = 0; // expected-error {{expression is not assignable}} 663201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl (i1 ? i1 : throw 0) = 0; // expected-error {{expression is not assignable}} 673201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl 683201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // p3 (one or both class type, convert to each other) 693201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // b1 (lvalues) 703201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl Base base; 713201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl Derived derived; 723201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl Convertible conv; 7376458501a8963fa11b91c9337a487de6871169b4Sebastian Redl Base &bar1 = i1 ? base : derived; 7476458501a8963fa11b91c9337a487de6871169b4Sebastian Redl Base &bar2 = i1 ? derived : base; 7576458501a8963fa11b91c9337a487de6871169b4Sebastian Redl Base &bar3 = i1 ? base : conv; 7676458501a8963fa11b91c9337a487de6871169b4Sebastian Redl Base &bar4 = i1 ? conv : base; 773201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // these are ambiguous 783201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl BadBase bb; 793201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl BadDerived bd; 803201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl (void)(i1 ? bb : bd); // expected-error {{conditional expression is ambiguous; 'struct BadBase' can be converted to 'struct BadDerived' and vice versa}} 813201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl (void)(i1 ? bd : bb); // expected-error {{conditional expression is ambiguous}} 823201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // curiously enough (and a defect?), these are not 833201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // for rvalues, hierarchy takes precedence over other conversions 843201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl (void)(i1 ? BadBase() : BadDerived()); 853201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl (void)(i1 ? BadDerived() : BadBase()); 863201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl 873201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // b2.1 (hierarchy stuff) 883201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl const Base constret(); 893201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl const Derived constder(); 903201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // should use const overload 913201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl A a1((i1 ? constret() : Base()).trick()); 923201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl A a2((i1 ? Base() : constret()).trick()); 933201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl A a3((i1 ? constret() : Derived()).trick()); 943201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl A a4((i1 ? Derived() : constret()).trick()); 953201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // should use non-const overload 963201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl i1 = (i1 ? Base() : Base()).trick(); 973201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl i1 = (i1 ? Base() : Base()).trick(); 983201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl i1 = (i1 ? Base() : Derived()).trick(); 993201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl i1 = (i1 ? Derived() : Base()).trick(); 1003201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // should fail: const lost 1013201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl (void)(i1 ? Base() : constder()); // expected-error {{incompatible operand types ('struct Base' and 'struct Derived const')}} 1023201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl (void)(i1 ? constder() : Base()); // expected-error {{incompatible operand types ('struct Derived const' and 'struct Base')}} 10376458501a8963fa11b91c9337a487de6871169b4Sebastian Redl // FIXME: should fail: private or ambiguous base 1043201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl (void)(i1 ? Base() : Priv()); // xpected-error private base 1053201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl (void)(i1 ? Priv() : Base()); // xpected-error private base 1063201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl (void)(i1 ? Base() : Fin()); // xpected-error ambiguous base 1073201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl (void)(i1 ? Fin() : Base()); // xpected-error ambiguous base 1083201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl 1093201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // b2.2 (non-hierarchy) 1103201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl i1 = i1 ? I() : i1; 1113201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl i1 = i1 ? i1 : I(); 1123201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl I i2(i1 ? I() : J()); 1133201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl I i3(i1 ? J() : I()); 1143201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // "the type [it] woud have if E2 were converted to an rvalue" 1153201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl vfn pfn = i1 ? F() : test; 1163201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl pfn = i1 ? test : F(); 1173201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // these are ambiguous - better messages would be nice 1183201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl (void)(i1 ? A() : B()); // expected-error {{incompatible operand types}} 1193201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl (void)(i1 ? B() : A()); // expected-error {{incompatible operand types}} 1203201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl (void)(i1 ? 1 : Ambig()); // expected-error {{incompatible operand types}} 1213201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl (void)(i1 ? Ambig() : 1); // expected-error {{incompatible operand types}} 12276458501a8963fa11b91c9337a487de6871169b4Sebastian Redl // By the way, this isn't an lvalue: 12376458501a8963fa11b91c9337a487de6871169b4Sebastian Redl &(i1 ? i1 : i2); // expected-error {{address expression must be an lvalue or a function designator}} 1243201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl 1253201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // p4 (lvalue, same type) 12676458501a8963fa11b91c9337a487de6871169b4Sebastian Redl Fields flds; 12776458501a8963fa11b91c9337a487de6871169b4Sebastian Redl int &ir1 = i1 ? flds.i1 : flds.i2; 12876458501a8963fa11b91c9337a487de6871169b4Sebastian Redl (i1 ? flds.b1 : flds.i2) = 0; 12976458501a8963fa11b91c9337a487de6871169b4Sebastian Redl (i1 ? flds.i1 : flds.b2) = 0; 13076458501a8963fa11b91c9337a487de6871169b4Sebastian Redl (i1 ? flds.b1 : flds.b2) = 0; 1313201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl 1323201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // p5 (conversion to built-in types) 1333201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // GCC 4.3 fails these 1343201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl double d1 = i1 ? I() : K(); 1353201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl pfn = i1 ? F() : G(); 13676458501a8963fa11b91c9337a487de6871169b4Sebastian Redl DFnPtr pfm; 13776458501a8963fa11b91c9337a487de6871169b4Sebastian Redl // FIXME: Overload resolution won't choose the member pointer yet. 13876458501a8963fa11b91c9337a487de6871169b4Sebastian Redl //pfm = i1 ? DFnPtr() : &Base::fn1; 13976458501a8963fa11b91c9337a487de6871169b4Sebastian Redl //pfm = i1 ? &Base::fn1 : DFnPtr(); 1403201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl 1413201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // p6 (final conversions) 1423201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl i1 = i1 ? i1 : ir1; 1433201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl int *pi1 = i1 ? &i1 : 0; 1443201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl pi1 = i1 ? 0 : &i1; 1453201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl i1 = i1 ? i1 : EVal; 1463201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl i1 = i1 ? EVal : i1; 1473201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl d1 = i1 ? 'c' : 4.0; 1483201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl d1 = i1 ? 4.0 : 'c'; 14976458501a8963fa11b91c9337a487de6871169b4Sebastian Redl pfm = i1 ? &Derived::fn2 : 0; 15076458501a8963fa11b91c9337a487de6871169b4Sebastian Redl pfm = i1 ? 0 : &Derived::fn2; 15176458501a8963fa11b91c9337a487de6871169b4Sebastian Redl // FIXME: pointer conversions don't work yet. 15276458501a8963fa11b91c9337a487de6871169b4Sebastian Redl //Base *pb = i1 ? (Base*)0 : (Derived*)0; 15376458501a8963fa11b91c9337a487de6871169b4Sebastian Redl //Base *pb = i1 ? (Derived*)0 : (Base*)0; 15476458501a8963fa11b91c9337a487de6871169b4Sebastian Redl //pfm = i1 ? &Base::fn1 : &Derived::fn2; 15576458501a8963fa11b91c9337a487de6871169b4Sebastian Redl //pfm = i1 ? &Derived::fn2 : &Base::fn1; 15676458501a8963fa11b91c9337a487de6871169b4Sebastian Redl // Conversion of primitives does not result in an lvalue. 15776458501a8963fa11b91c9337a487de6871169b4Sebastian Redl &(i1 ? i1 : d1); // expected-error {{address expression must be an lvalue or a function designator}} 15876458501a8963fa11b91c9337a487de6871169b4Sebastian Redl 1593201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl 1603201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // Note the thing that this does not test: since DR446, various situations 1613201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // *must* create a separate temporary copy of class objects. This can only 1623201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl // be properly tested at runtime, though. 1633201f6beec688ab9fe8750527e28f52d5420e22dSebastian Redl} 164