id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
7381	C++11 compliance: unresolved symbol when assigning a constexpr duration to a non-const local variable	viboes	viboes	"When assigning a template static value member of type constexpr boost::chrono::duration to a non-const local variable

{{{

template <int Val, typename Type>
struct dummy
{
  typedef Type type;
  static constexpr type value{static_cast<type>(Val)};
};

void aTest(){
   auto z3 = dummy2<7,boost::chrono::hours>::value;
}

}}}

There is an unresolved symbol link error.

The reason is that the boost::chrono::duration copy constructor must be =default on c++11 so that the type can be used as a constexpr.

Removing the following declaration in boost/chrono/duration

{{{
  BOOST_CONSTEXPR duration(const duration& rhs) : rep_(rhs.rep_) {} // = default;
}}}

solves the issue.
"	Bugs	closed	Boost 1.52.0	chrono	Boost 1.51.0	Problem	fixed	constexpr duration