clang/test/SemaTemplate/instantiate-exception-spec-cxx11.cpp

   1 // RUN: %clang_cc1 -fsyntax-only -verify -triple %itanium_abi_triple -std=c++11 -ftemplate-depth 16 -fcxx-exceptions -fexceptions %s
   2
   3 // DR1330: an exception specification for a function template is only
   4 // instantiated when it is needed.
   5
   6 // Note: the test is Itanium-specific because it depends on key functions in the
   7 // PR12763 namespace.
   8
   9 template<typename T> void f1(T*) throw(T); // expected-error{{incomplete type 'Incomplete' is not allowed in exception specification}}
  10 struct Incomplete; // expected-note{{forward}}
  11
  12 void test_f1(Incomplete *incomplete_p, int *int_p) {
  13   f1(int_p);
  14   f1(incomplete_p); // expected-note{{instantiation of exception spec}}
  15 }
  16
  17 template<typename T> struct A {
  18   template<typename U> struct B {
  19     static void f() noexcept(A<U>().n);
  20   };
  21
  22   constexpr A() : n(true) {}
  23   bool n;
  24 };
  25
  26 static_assert(noexcept(A<int>::B<char>::f()), "");
  27
  28 template<unsigned N> struct S {
  29   static void recurse() noexcept(noexcept(S<N+1>::recurse())); // \
  30   // expected-error {{no member named 'recurse'}} \
  31   // expected-note 9{{instantiation of exception spec}}
  32 };
  33
  34 template<> struct S<10> {};
  35 void (*pFn2)() noexcept = &S<0>::recurse; // expected-note {{instantiation of exception spec}} expected-error {{not superset}}
  36
  37
  38 namespace dr1330_example {
  39   template <class T> struct A {
  40     void f(...) throw (typename T::X);
  41     void f(int);
  42   };
  43
  44   int main() {
  45     A<int>().f(42);
  46   }
  47
  48   struct S {
  49     template<typename T> static void f() throw(typename T::X);
  50     typedef decltype(f<S>()) X; // expected-error {{exception specification is not available}}
  51   };
  52
  53   struct T {
  54     template<typename T> static void f() throw(T**);
  55     typedef decltype(f<S>()) X; // expected-error {{exception specification is not available}}
  56   };
  57
  58   template<typename T>
  59   struct U {
  60     void f() noexcept(T::error);
  61     void (g)() noexcept(T::error);
  62   };
  63   U<int> uint; // ok
  64 }
  65
  66 namespace core_19754_example {
  67   template<typename T> T declval() noexcept;
  68
  69   template<typename T, typename = decltype(T(declval<T&&>()))>
  70   struct is_movable { static const bool value = true; };
  71
  72   template<typename T>
  73   struct wrap {
  74     T val;
  75     void irrelevant(wrap &p) noexcept(is_movable<T>::value);
  76   };
  77
  78   template<typename T>
  79   struct base {
  80      base() {}
  81      base(const typename T::type1 &);
  82      base(const typename T::type2 &);
  83   };
  84
  85   template<typename T>
  86   struct type1 {
  87      wrap<typename T::base> base;
  88   };
  89
  90   template<typename T>
  91   struct type2 {
  92      wrap<typename T::base> base;
  93   };
  94
  95   struct types {
  96      typedef base<types> base;
  97      typedef type1<types> type1;
  98      typedef type2<types> type2;
  99   };
 100
 101   base<types> val = base<types>();
 102 }
 103
 104 namespace pr9485 {
 105   template <typename T> void f1(T) throw(typename T::exception); // expected-note {{candidate}}
 106   template <typename T> void f1(T, int = 0) throw(typename T::noitpecxe); // expected-note {{candidate}}
 107
 108   template <typename T> void f2(T) noexcept(T::throws); // expected-note {{candidate}}
 109   template <typename T> void f2(T, int = 0) noexcept(T::sworht); // expected-note {{candidate}}
 110
 111   void test() {
 112     f1(0); // expected-error {{ambiguous}}
 113     f2(0); // expected-error {{ambiguous}}
 114   }
 115 }
 116
 117 struct Exc1 { char c[4]; };
 118 struct Exc2 { double x, y, z; };
 119 struct Base {
 120   virtual void f() noexcept; // expected-note {{overridden}}
 121 };
 122 template<typename T> struct Derived : Base {
 123   void f() noexcept (sizeof(T) == 4); // expected-error {{is more lax}}
 124   void g() noexcept (T::error);
 125 };
 126
 127 Derived<Exc1> d1; // ok
 128 Derived<Exc2> d2; // expected-note {{in instantiation of}}
 129
 130 // If the vtable for a derived class is used, the exception specification of
 131 // any member function which ends up in that vtable is needed, even if it was
 132 // declared in a base class.
 133 namespace PR12763 {
 134   template<bool *B> struct T {
 135     virtual void f() noexcept (*B); // expected-error {{constant expression}} expected-note {{read of non-const}}
 136   };
 137   bool b; // expected-note {{here}}
 138   struct X : public T<&b> {
 139     virtual void g();
 140   };
 141   void X::g() {} // expected-note {{in instantiation of}}
 142 }
 143
 144 namespace Variadic {
 145   template<bool B> void check() { static_assert(B, ""); }
 146   template<bool B, bool B2, bool ...Bs> void check() { static_assert(B, ""); check<B2, Bs...>(); }
 147
 148   template<typename ...T> void consume(T...);
 149
 150   template<typename ...T> void f(void (*...p)() throw (T)) {
 151     void (*q[])() = { p... };
 152     consume((p(),0)...);
 153   }
 154   template<bool ...B> void g(void (*...p)() noexcept (B)) {
 155     consume((p(),0)...);
 156     check<noexcept(p()) == B ...>();
 157   }
 158   template<typename ...T> void i() {
 159     consume([]() throw(T) {} ...);
 160     consume([]() noexcept(sizeof(T) == 4) {} ...);
 161   }
 162   template<bool ...B> void j() {
 163     consume([](void (*p)() noexcept(B)) {
 164       void (*q)() noexcept = p; // expected-error {{not superset of source}}
 165     } ...);
 166   }
 167
 168   void z() {
 169     f<int, char, double>(nullptr, nullptr, nullptr);
 170     g<true, false, true>(nullptr, nullptr, nullptr);
 171     i<int, long, short>();
 172     j<true, true>();
 173     j<true, false>(); // expected-note {{in instantiation of}}
 174   }
 175
 176 }
 177
 178 namespace NondefDecls {
 179   template<typename T> void f1() {
 180     int g1(int) noexcept(T::error); // expected-error{{type 'int' cannot be used prior to '::' because it has no members}}
 181   }
 182   template void f1<int>(); // expected-note{{in instantiation of function template specialization 'NondefDecls::f1<int>' requested here}}
 183 }
 184