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      1 // RUN: %clang_cc1 -fsyntax-only -fcxx-exceptions -verify -std=c++11 -Wall %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 be used by non-static data member initializer}}
     21   };
     22   // We can use it now.
     23   bool w = noexcept(ConstExpr());
     24 
     25   // Much more obviously broken: we can't parse the initializer without already
     26   // knowing whether it produces a noexcept expression.
     27   struct TemplateArg {
     28     int n = ExceptionIf<noexcept(TemplateArg())>::f(); // expected-error {{cannot be used by non-static data member initializer}}
     29   };
     30   bool x = noexcept(TemplateArg());
     31 
     32   // And within a nested class.
     33   struct Nested { // expected-error {{cannot be used by non-static data member initializer}}
     34     struct Inner {
     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 {
     40     struct Inner;
     41     int n = Inner().n; // expected-error {{cannot be used by non-static data member initializer}}
     42     struct Inner {
     43       int n = ExceptionIf<noexcept(Nested2())>::f();
     44     } inner;
     45   };
     46 }
     47 
     48 namespace ExceptionSpecification {
     49   // A type is permitted to be used in a dynamic exception specification when it
     50   // is still being defined, but isn't complete within such an exception
     51   // specification.
     52   struct Nested { // expected-note {{not complete}}
     53     struct T {
     54       T() noexcept(!noexcept(Nested())); // expected-error{{incomplete type}}
     55     } t;
     56   };
     57 }
     58 
     59 namespace DefaultArgument {
     60   struct Default {
     61     struct T {
     62       T(int = ExceptionIf<noexcept(Default())::f()); // expected-error {{call to implicitly-deleted default constructor}}
     63     } t; // expected-note {{has no default constructor}}
     64   };
     65 }
     66 
     67 namespace ImplicitDtorExceptionSpec {
     68   struct A {
     69     virtual ~A();
     70 
     71     struct Inner {
     72       ~Inner() throw();
     73     };
     74     Inner inner;
     75   };
     76 
     77   struct B {
     78     virtual ~B() {} // expected-note {{here}}
     79   };
     80 
     81   struct C : B {
     82     virtual ~C() {}
     83     A a;
     84   };
     85 
     86   struct D : B {
     87     ~D(); // expected-error {{more lax than base}}
     88     struct E {
     89       ~E();
     90       struct F {
     91         ~F() throw(A);
     92       } f;
     93     } e;
     94   };
     95 }
     96