gcc/testsuite/g++.dg/cpp0x/constexpr-52892-1.C

   1 // PR c++/52892
   2 // { dg-do compile { target c++11 } }
   3
   4 constexpr __SIZE_TYPE__ fibonacci(__SIZE_TYPE__ val) {
   5   return (val <= 2) ? 1 : fibonacci(val - 1) + fibonacci(val - 2);
   6 }
   7
   8 template <typename Function>
   9 struct Defer {
  10   constexpr Defer(const Function func_) : func(func_) { }
  11
  12   const Function func;
  13
  14   template <typename... Args>
  15   constexpr auto operator () (const Args&... args) -> decltype(func(args...)) {
  16     return func(args...);
  17   }
  18 };
  19
  20 template <typename Function>
  21 constexpr Defer<Function> make_deferred(const Function f) {
  22   return Defer<Function>(f);
  23 }
  24
  25 int main() {
  26   constexpr auto deferred = make_deferred(&fibonacci);
  27   static_assert(deferred(25) == 75025, "Static fibonacci call failed"); // { dg-error "no match for call" "" { target c++14 } }
  28 }