clang/test/SemaCXX/auto-type-from-cxx.cpp

   1 // RUN: %clang_cc1 -std=c++14 -fsyntax-only -verify %s
   2
   3 struct A {
   4     operator __auto_type() {} // expected-error {{'__auto_type' not allowed in conversion function type}}
   5 };
   6
   7 __auto_type a() -> int; // expected-error {{function with trailing return type must specify return type 'auto'}}
   8 __auto_type a2(); // expected-error {{'__auto_type' not allowed in function return type}}
   9 template <typename T>
  10 __auto_type b() { return T::x; } // expected-error {{'__auto_type' not allowed in function return type}}
  11 auto c() -> __auto_type { __builtin_unreachable(); } // expected-error {{'__auto_type' not allowed in function return type}}
  12 int d() {
  13   decltype(__auto_type) e = 1; // expected-error {{expected expression}}
  14   auto _ = [](__auto_type f) {}; // expected-error {{'__auto_type' not allowed in lambda parameter}}
  15   __auto_type g = 2;
  16   struct BitField { int field:2; };
  17   __auto_type h = BitField{1}.field; // (should work from C++)
  18   new __auto_type; // expected-error {{'__auto_type' not allowed in type allocated by 'new'}}
  19 }
  20
  21 namespace TestDeductionFail {
  22
  23 template<typename T>
  24 void caller(T x) {x.fun();} // expected-error {{parameter type 'TestDeductionFail::Abstract' is an abstract class}}
  25
  26 template<typename T>
  27 auto getCaller(){
  28   return caller<T>; // expected-note {{in instantiation of function template specialization 'TestDeductionFail::caller<TestDeductionFail::Abstract>' requested here}}
  29 }
  30
  31 class Abstract{
  32   public:
  33     void fun();
  34     virtual void vfun()=0; // expected-note {{unimplemented pure virtual method 'vfun' in 'Abstract'}}
  35     void call(){getCaller<Abstract>()(*this);} // expected-error {{allocating an object of abstract class type 'TestDeductionFail::Abstract'}}
  36 };
  37
  38 }