gcc-4.9/gcc/testsuite/g++.dg/template/sfinae16.C


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// PR c++/41927
// { dg-do compile { target c++11 } }
// { dg-options "-Wall" }

// We were getting a spurious ||/&& warning about the enable_if with the
// source position of d1.

template<typename Tp>
  struct is_int
  { static const bool value = true; };

template<bool, typename Tp = void>
  struct enable_if
  { };

template<typename Tp>
  struct enable_if<true, Tp>
  { typedef Tp type; };

template<typename Rep>
  struct duration
  {
    duration() { }

    template<typename Rep2, typename = typename
             enable_if<false || (true && is_int<Rep2>::value)>::type>
    duration(const duration<Rep2>&) { }
  };

int main()
{
  duration<int> d0;
  duration<int> d1 = d0;	// { dg-warning "set but not used" }
}