llvm-project/clang/test/SemaCXX/conditional-expr.cpp

430 lines
14 KiB
C++

// RUN: %clang_cc1 -fcxx-exceptions -fexceptions -fsyntax-only -verify=expected,expected-cxx11 -std=c++11 -Wsign-conversion %s
// RUN: %clang_cc1 -fcxx-exceptions -fexceptions -fsyntax-only -verify=expected,expected-cxx17 -std=c++17 -Wsign-conversion %s
// C++ rules for ?: are a lot stricter than C rules, and have to take into
// account more conversion options.
// This test runs in C++11 mode for the contextual conversion of the condition.
struct ToBool { explicit operator bool(); };
struct B;
struct A {
A();
A(const B&); // expected-note 2 {{candidate constructor}}
};
struct B { operator A() const; }; // expected-note 2 {{candidate function}}
struct I { operator int(); };
struct J { operator I(); };
struct K { operator double(); };
typedef void (*vfn)();
struct F { operator vfn(); };
struct G { operator vfn(); };
struct Base {
int trick();
A trick() const;
void fn1();
};
struct Derived : Base {
void fn2();
};
struct Convertible { operator Base&(); };
struct Priv : private Base {}; // expected-note 4 {{declared private here}}
struct Mid : Base {};
struct Fin : Mid, Derived {};
typedef void (Derived::*DFnPtr)();
struct ToMemPtr { operator DFnPtr(); };
struct BadDerived;
struct BadBase { operator BadDerived&(); };
struct BadDerived : BadBase {};
struct Fields {
int i1, i2, b1 : 3, b2 : 3;
};
struct MixedFields {
int i;
volatile int vi;
const int ci;
const volatile int cvi;
};
struct MixedFieldsDerived : MixedFields {
};
enum Enum { EVal };
struct Ambig {
operator short(); // expected-note 2 {{candidate function}}
operator signed char(); // expected-note 2 {{candidate function}}
};
struct Abstract {
virtual ~Abstract() = 0; // expected-note {{unimplemented pure virtual method '~Abstract' in 'Abstract'}}
};
struct Derived1: Abstract {
};
struct Derived2: Abstract {
};
void test()
{
// This function tests C++0x 5.16
// p1 (contextually convert to bool)
int i1 = ToBool() ? 0 : 1;
// p2 (one or both void, and throwing)
Fields flds;
i1 ? throw 0 : throw 1;
i1 ? test() : throw 1;
i1 ? throw 0 : test();
i1 ? test() : test();
i1 = i1 ? throw 0 : 0;
i1 = i1 ? 0 : throw 0;
i1 = i1 ? (throw 0) : 0;
i1 = i1 ? 0 : (throw 0);
i1 ? 0 : test(); // expected-error {{right operand to ? is void, but left operand is of type 'int'}}
i1 ? test() : 0; // expected-error {{left operand to ? is void, but right operand is of type 'int'}}
(i1 ? throw 0 : i1) = 0;
(i1 ? i1 : throw 0) = 0;
(i1 ? (throw 0) : i1) = 0;
(i1 ? i1 : (throw 0)) = 0;
(i1 ? (void)(throw 0) : i1) = 0; // expected-error {{left operand to ? is void, but right operand is of type 'int'}}
(i1 ? i1 : (void)(throw 0)) = 0; // expected-error {{right operand to ? is void, but left operand is of type 'int'}}
int &throwRef1 = (i1 ? flds.i1 : throw 0);
int &throwRef2 = (i1 ? throw 0 : flds.i1);
int &throwRef3 = (i1 ? flds.b1 : throw 0); // expected-error {{non-const reference cannot bind to bit-field}}
int &throwRef4 = (i1 ? throw 0 : flds.b1); // expected-error {{non-const reference cannot bind to bit-field}}
// p3 (one or both class type, convert to each other)
// b1 (lvalues)
Base base;
Derived derived;
Convertible conv;
Base &bar1 = i1 ? base : derived;
Base &bar2 = i1 ? derived : base;
Base &bar3 = i1 ? base : conv;
Base &bar4 = i1 ? conv : base;
// these are ambiguous
BadBase bb;
BadDerived bd;
(void)(i1 ? bb : bd); // expected-error {{conditional expression is ambiguous; 'BadBase' can be converted to 'BadDerived' and vice versa}}
(void)(i1 ? bd : bb); // expected-error {{conditional expression is ambiguous}}
// curiously enough (and a defect?), these are not
// for rvalues, hierarchy takes precedence over other conversions
(void)(i1 ? BadBase() : BadDerived());
(void)(i1 ? BadDerived() : BadBase());
// b2.1 (hierarchy stuff)
extern const Base constret();
extern const Derived constder();
// should use const overload
A a1((i1 ? constret() : Base()).trick());
A a2((i1 ? Base() : constret()).trick());
A a3((i1 ? constret() : Derived()).trick());
A a4((i1 ? Derived() : constret()).trick());
// should use non-const overload
i1 = (i1 ? Base() : Base()).trick();
i1 = (i1 ? Base() : Base()).trick();
i1 = (i1 ? Base() : Derived()).trick();
i1 = (i1 ? Derived() : Base()).trick();
// should fail: const lost
(void)(i1 ? Base() : constder()); // expected-error {{incompatible operand types ('Base' and 'const Derived')}}
(void)(i1 ? constder() : Base()); // expected-error {{incompatible operand types ('const Derived' and 'Base')}}
Priv priv;
Fin fin;
(void)(i1 ? Base() : Priv()); // expected-error{{private base class}}
(void)(i1 ? Priv() : Base()); // expected-error{{private base class}}
(void)(i1 ? Base() : Fin()); // expected-error{{ambiguous conversion from derived class 'Fin' to base class 'Base':}}
(void)(i1 ? Fin() : Base()); // expected-error{{ambiguous conversion from derived class 'Fin' to base class 'Base':}}
(void)(i1 ? base : priv); // expected-error {{private base class}}
(void)(i1 ? priv : base); // expected-error {{private base class}}
(void)(i1 ? base : fin); // expected-error {{ambiguous conversion from derived class 'Fin' to base class 'Base':}}
(void)(i1 ? fin : base); // expected-error {{ambiguous conversion from derived class 'Fin' to base class 'Base':}}
// b2.2 (non-hierarchy)
i1 = i1 ? I() : i1;
i1 = i1 ? i1 : I();
I i2(i1 ? I() : J());
I i3(i1 ? J() : I());
// "the type [it] would have if E2 were converted to an rvalue"
vfn pfn = i1 ? F() : test;
pfn = i1 ? test : F();
(void)(i1 ? A() : B()); // expected-error {{conversion from 'B' to 'A' is ambiguous}}
(void)(i1 ? B() : A()); // expected-error {{conversion from 'B' to 'A' is ambiguous}}
(void)(i1 ? 1 : Ambig()); // expected-error {{conversion from 'Ambig' to 'int' is ambiguous}}
(void)(i1 ? Ambig() : 1); // expected-error {{conversion from 'Ambig' to 'int' is ambiguous}}
// By the way, this isn't an lvalue:
&(i1 ? i1 : i2); // expected-error {{cannot take the address of an rvalue}}
// p4 (lvalue, same type)
int &ir1 = i1 ? flds.i1 : flds.i2;
(i1 ? flds.b1 : flds.i2) = 0;
(i1 ? flds.i1 : flds.b2) = 0;
(i1 ? flds.b1 : flds.b2) = 0;
// p5 (conversion to built-in types)
// GCC 4.3 fails these
double d1 = i1 ? I() : K();
pfn = i1 ? F() : G();
DFnPtr pfm;
pfm = i1 ? DFnPtr() : &Base::fn1;
pfm = i1 ? &Base::fn1 : DFnPtr();
// p6 (final conversions)
i1 = i1 ? i1 : ir1;
int *pi1 = i1 ? &i1 : 0;
pi1 = i1 ? 0 : &i1;
i1 = i1 ? i1 : EVal;
i1 = i1 ? EVal : i1;
d1 = i1 ? 'c' : 4.0;
d1 = i1 ? 4.0 : 'c';
Base *pb = i1 ? (Base*)0 : (Derived*)0;
pb = i1 ? (Derived*)0 : (Base*)0;
pfm = i1 ? &Base::fn1 : &Derived::fn2;
pfm = i1 ? &Derived::fn2 : &Base::fn1;
pfm = i1 ? &Derived::fn2 : 0;
pfm = i1 ? 0 : &Derived::fn2;
const int (MixedFieldsDerived::*mp1) =
i1 ? &MixedFields::ci : &MixedFieldsDerived::i;
const volatile int (MixedFields::*mp2) =
i1 ? &MixedFields::ci : &MixedFields::cvi;
(void)(i1 ? &MixedFields::ci : &MixedFields::vi);
// Conversion of primitives does not result in an lvalue.
&(i1 ? i1 : d1); // expected-error {{cannot take the address of an rvalue}}
(void)&(i1 ? flds.b1 : flds.i1); // expected-error {{address of bit-field requested}}
(void)&(i1 ? flds.i1 : flds.b1); // expected-error {{address of bit-field requested}}
unsigned long test0 = 5;
test0 = test0 ? (long) test0 : test0; // expected-warning {{operand of ? changes signedness: 'long' to 'unsigned long'}}
test0 = test0 ? (int) test0 : test0; // expected-warning {{operand of ? changes signedness: 'int' to 'unsigned long'}}
test0 = test0 ? (short) test0 : test0; // expected-warning {{operand of ? changes signedness: 'short' to 'unsigned long'}}
test0 = test0 ? test0 : (long) test0; // expected-warning {{operand of ? changes signedness: 'long' to 'unsigned long'}}
test0 = test0 ? test0 : (int) test0; // expected-warning {{operand of ? changes signedness: 'int' to 'unsigned long'}}
test0 = test0 ? test0 : (short) test0; // expected-warning {{operand of ? changes signedness: 'short' to 'unsigned long'}}
test0 = test0 ? test0 : (long) 10;
test0 = test0 ? test0 : (int) 10;
test0 = test0 ? test0 : (short) 10;
test0 = test0 ? (long) 10 : test0;
test0 = test0 ? (int) 10 : test0;
test0 = test0 ? (short) 10 : test0;
int test1;
test0 = test0 ? EVal : test0;
test1 = test0 ? EVal : (int) test0;
test0 = test0 ? EVal : test1; // expected-warning {{operand of ? changes signedness: 'int' to 'unsigned long'}}
test0 = test0 ? test1 : EVal; // expected-warning {{operand of ? changes signedness: 'int' to 'unsigned long'}}
test1 = test0 ? EVal : (int) test0;
test1 = test0 ? (int) test0 : EVal;
// Note the thing that this does not test: since DR446, various situations
// *must* create a separate temporary copy of class objects. This can only
// be properly tested at runtime, though.
const Abstract &abstract1 = true ? static_cast<const Abstract&>(Derived1()) : Derived2(); // expected-error {{allocating an object of abstract class type 'const Abstract'}}
const Abstract &abstract2 = true ? static_cast<const Abstract&>(Derived1()) : throw 3;
}
namespace PR6595 {
struct OtherString {
OtherString();
OtherString(const char*);
};
struct String {
String(const char *);
String(const OtherString&);
operator const char*() const;
};
void f(bool Cond, String S, OtherString OS) {
(void)(Cond? S : "");
(void)(Cond? "" : S);
const char a[1] = {'a'};
(void)(Cond? S : a);
(void)(Cond? a : S);
(void)(Cond? OS : S);
}
}
namespace PR6757 {
struct Foo1 {
Foo1();
Foo1(const Foo1&);
};
struct Foo2 { };
struct Foo3 {
Foo3(); // expected-note{{requires 0 arguments}}
Foo3(Foo3&); // expected-note{{would lose const qualifier}}
};
struct Bar {
operator const Foo1&() const;
operator const Foo2&() const;
operator const Foo3&() const;
};
void f() {
(void)(true ? Bar() : Foo1()); // okay
(void)(true ? Bar() : Foo2()); // okay
(void)(true ? Bar() : Foo3()); // expected-error{{no viable constructor copying temporary}}
}
}
// Reduced from selfhost.
namespace test1 {
struct A {
enum Foo {
fa, fb, fc, fd, fe, ff
};
Foo x();
};
void foo(int);
void test(A *a) {
foo(a ? a->x() : 0);
}
}
namespace rdar7998817 {
class X {
X(X&); // expected-note{{declared private here}}
struct ref { };
public:
X();
X(ref);
operator ref();
};
void f(bool B) {
X x;
(void)(B? x // expected-error{{calling a private constructor of class 'rdar7998817::X'}}
: X());
}
}
namespace PR7598 {
enum Enum {
v = 1,
};
const Enum g() {
return v;
}
const volatile Enum g2() {
return v;
}
void f() {
const Enum v2 = v;
Enum e = false ? g() : v;
Enum e2 = false ? v2 : v;
Enum e3 = false ? g2() : v;
}
}
namespace PR9236 {
#define NULL 0L
void f() {
int i;
(void)(true ? A() : NULL); // expected-error{{non-pointer operand type 'A' incompatible with NULL}}
(void)(true ? NULL : A()); // expected-error{{non-pointer operand type 'A' incompatible with NULL}}
(void)(true ? 0 : A()); // expected-error{{incompatible operand types}}
(void)(true ? nullptr : A()); // expected-error{{non-pointer operand type 'A' incompatible with nullptr}}
(void)(true ? nullptr : i); // expected-error{{non-pointer operand type 'int' incompatible with nullptr}}
(void)(true ? __null : A()); // expected-error{{non-pointer operand type 'A' incompatible with NULL}}
(void)(true ? (void*)0 : A()); // expected-error{{incompatible operand types}}
}
}
namespace DR587 {
template<typename T>
const T *f(bool b) {
static T t1 = T();
static const T t2 = T();
return &(b ? t1 : t2);
}
struct S {};
template const int *f(bool);
template const S *f(bool);
extern bool b;
int i = 0;
const int ci = 0;
volatile int vi = 0;
const volatile int cvi = 0;
const int &cir = b ? i : ci;
volatile int &vir = b ? vi : i;
const volatile int &cvir1 = b ? ci : cvi;
const volatile int &cvir2 = b ? cvi : vi;
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'}}
}
namespace PR17052 {
struct X {
int i_;
bool b_;
int &test() { return b_ ? i_ : throw 1; }
};
}
namespace PR26448 {
struct Base {};
struct Derived : Base {};
Base b;
Derived d;
typedef decltype(true ? static_cast<Base&&>(b) : static_cast<Derived&&>(d)) x;
typedef Base &&x;
}
namespace lifetime_extension {
struct A {};
struct B : A { B(); ~B(); };
struct C : A { C(); ~C(); };
void f(bool b) {
A &&r = b ? static_cast<A&&>(B()) : static_cast<A&&>(C());
}
struct D { A &&a; };
void f_indirect(bool b) {
D d = b ? D{B()} // expected-cxx11-warning {{temporary whose address is used as value of local variable 'd' will be destroyed at the end of the full-expression}}
: D{C()}; // expected-cxx11-warning {{temporary whose address is used as value of local variable 'd' will be destroyed at the end of the full-expression}}
}
}
namespace PR46484 {
// expected-error@+4{{expected ':'}}
// expected-note@+3{{to match this '?'}}
// expected-warning@+2{{variable 'b' is uninitialized}}
// expected-error@+1 2 {{expected ';' after top level declarator}}
int a long b = a = b ? throw 0 1
void g() {
extern int a;
extern long b;
long c = a = b ? throw 0 : 1;
long d = a = b ? 1 : throw 0;
// expected-error@+1 {{assigning to 'int' from incompatible type 'void'}}
long e = a = b ? throw 0 : throw 1;
}
} // namespace PR46484