1 // RUN: %clang_cc1 -fsyntax-only -fcxx-exceptions -verify -std=c++11 -Wall -Wno-unused-local-typedefs %s 2 3 template<bool b> struct ExceptionIf { static int f(); }; 4 template<> struct ExceptionIf<false> { typedef int f; }; 5 6 // The exception specification of a defaulted default constructor depends on 7 // the contents of in-class member initializers. However, the in-class member 8 // initializers can depend on the exception specification of the constructor, 9 // since the class is considered complete within them. We reject any such cases. 10 namespace InClassInitializers { 11 // Noexcept::Noexcept() is implicitly declared as noexcept(false), because it 12 // directly invokes ThrowSomething(). However... 13 // 14 // If noexcept(Noexcept()) is false, then Noexcept() is a constant expression, 15 // so noexcept(Noexcept()) is true. But if noexcept(Noexcept()) is true, then 16 // Noexcept::Noexcept is not declared constexpr, therefore noexcept(Noexcept()) 17 // is false. 18 bool ThrowSomething() noexcept(false); 19 struct ConstExpr { 20 bool b = noexcept(ConstExpr()) && ThrowSomething(); // expected-error {{cannot use defaulted default constructor of 'ConstExpr' within the class outside of member functions}} 21 // expected-note@-1 {{implicit default constructor for 'InClassInitializers::ConstExpr' first required here}} 22 }; 23 24 // Much more obviously broken: we can't parse the initializer without already 25 // knowing whether it produces a noexcept expression. 26 struct TemplateArg { 27 int n = ExceptionIf<noexcept(TemplateArg())>::f(); // expected-error {{cannot use defaulted default constructor of 'TemplateArg' within the class outside of member functions}} 28 // expected-note@-1 {{implicit default constructor for 'InClassInitializers::TemplateArg' first required here}} 29 }; 30 31 // And within a nested class. 32 struct Nested { // expected-note {{implicit default constructor for 'InClassInitializers::Nested::Inner' first required here}} 33 struct Inner { 34 // expected-error@+1 {{cannot use defaulted default constructor of 'Inner' within 'Nested' outside of member functions}} 35 int n = ExceptionIf<noexcept(Nested())>::f(); // expected-note {{implicit default constructor for 'InClassInitializers::Nested' first required here}} 36 } inner; 37 }; 38 39 struct Nested2 { // expected-error {{implicit default constructor for 'InClassInitializers::Nested2' must explicitly initialize the member 'inner' which does not have a default constructor}} 40 struct Inner; 41 int n = Inner().n; // expected-note {{implicit default constructor for 'InClassInitializers::Nested2::Inner' first required here}} 42 struct Inner { // expected-note {{declared here}} 43 // expected-error@+1 {{cannot use defaulted default constructor of 'Inner' within 'Nested2' outside of member functions}} 44 int n = ExceptionIf<noexcept(Nested2())>::f(); 45 // expected-note@-1 {{implicit default constructor for 'InClassInitializers::Nested2' first required here}} 46 } inner; // expected-note {{member is declared here}} 47 }; 48 } 49 50 namespace ExceptionSpecification { 51 // FIXME: This diagnostic is quite useless; we should indicate whose 52 // exception specification we were looking for and why. 53 struct Nested { 54 struct T { 55 T() noexcept(!noexcept(Nested())); 56 } t; // expected-error{{exception specification is not available until end of class definition}} 57 }; 58 } 59 60 namespace DefaultArgument { 61 struct Default { 62 struct T { 63 T(int = ExceptionIf<noexcept(Default())::f()); // expected-error {{call to implicitly-deleted default constructor}} 64 } t; // expected-note {{has no default constructor}} 65 }; 66 } 67 68 namespace ImplicitDtorExceptionSpec { 69 struct A { 70 virtual ~A(); 71 72 struct Inner { 73 ~Inner() throw(); 74 }; 75 Inner inner; 76 }; 77 78 struct B { 79 virtual ~B() {} // expected-note {{here}} 80 }; 81 82 struct C : B { 83 virtual ~C() {} 84 A a; 85 }; 86 87 struct D : B { 88 ~D(); // expected-error {{more lax than base}} 89 struct E { 90 ~E(); 91 struct F { 92 ~F() throw(A); 93 } f; 94 } e; 95 }; 96 } 97
