69 lines · cpp
1// RUN: %clang_cc1 -verify -std=c++11 %s2 3namespace N {4 typedef char C;5}6 7namespace M {8 typedef double D;9}10 11struct NonLiteral {12 NonLiteral() {}13 NonLiteral(int) {}14 operator int() const { return 0; }15};16struct Literal {17 constexpr Literal() {}18 operator int() const { return 0; }19};20 21struct S {22 virtual int ImplicitlyVirtual() const;23};24struct T {};25 26template<typename T> struct ImplicitVirtualFromDependentBase : T {27 constexpr int ImplicitlyVirtual() const { return 0; }28};29 30constexpr int a = ImplicitVirtualFromDependentBase<S>().ImplicitlyVirtual(); // expected-error {{constant expression}} expected-note {{cannot evaluate call to virtual function}}31constexpr int b = ImplicitVirtualFromDependentBase<T>().ImplicitlyVirtual(); // ok32constexpr int c = ImplicitVirtualFromDependentBase<S>().ImplicitVirtualFromDependentBase<S>::ImplicitlyVirtual(); // expected-error {{constant expression}} expected-note {{cannot evaluate call to virtual function}}33 34template<typename R> struct ConstexprMember {35 constexpr R F() const { return 0; }36};37constexpr int d = ConstexprMember<int>().F(); // ok38constexpr int e = ConstexprMember<NonLiteral>().F(); // expected-error {{constant expression}} expected-note {{non-literal type 'NonLiteral' cannot be used in a constant expression}}39 40template<typename ...P> struct ConstexprCtor {41 constexpr ConstexprCtor(P...) {}42};43constexpr ConstexprCtor<> f1() { return {}; } // ok44constexpr ConstexprCtor<int> f2() { return 0; } // ok45constexpr ConstexprCtor<NonLiteral> f3() { return { 0 }; } // expected-error {{never produces a constant expression}} expected-note {{non-literal type 'NonLiteral}}46constexpr ConstexprCtor<int, NonLiteral> f4() { return { 0, 0 }; } // expected-error {{never produces a constant expression}} expected-note {{non-literal type 'NonLiteral}}47 48struct VirtBase : virtual S {}; // expected-note {{here}}49 50namespace TemplateVBase {51 template<typename T> struct T1 : virtual Literal { // expected-note {{here}}52 constexpr T1() {} // expected-error {{constexpr constructor not allowed in struct with virtual base class}}53 };54 55 template<typename T> struct T2 : virtual T {56 // FIXME: This is ill-formed (no diagnostic required).57 // We should diagnose it now rather than waiting until instantiation.58 constexpr T2() {}59 };60 constexpr T2<Literal> g2() { return {}; }61 62 template<typename T> class T3 : public T { // expected-note {{class with virtual base class is not a literal type}}63 public:64 constexpr T3() {}65 };66 constexpr T3<Literal> g3() { return {}; } // ok67 constexpr T3<VirtBase> g4() { return {}; } // expected-error {{not a literal type}}68}69