[Boost-users] [context/coroutine] DLL link errors in VS2015

Subject: [Boost-users] [context/coroutine] DLL link errors in VS2015
From: Gavin Lambert (gavinl_at_[hidden])
Date: 2017-02-22 01:37:30

I'm migrating some existing code that uses Boost.Coroutine from VS2013 
to VS2015 and from Boost 1.55 to Boost 1.60.

(Minor aside: coroutine<T>::push_type had an empty() method in 1.55 
which has vanished in 1.60.  This was mildly annoying but easily fixed 
by using operator! instead.)

The code builds and runs fine as-is in VS2015 with Boost 1.60.  However 
I wanted to try migrating to Boost.Coroutine2 as well, since Coroutine 
is deprecated.  This however gives me the following errors:

t:\boost\boost_1_60_0\boost\context\execution_context.ipp(209): warning 
C4251: 'boost::context::execution_context::ptr_': class 
'boost::intrusive_ptr<boost::context::detail::activation_record>' needs 
to have dll-interface to be used by clients of class 
'boost::context::execution_context'
          t:\boost\boost_1_60_0\boost\context\execution_context.ipp(54): 
note: see declaration of 
'boost::intrusive_ptr<boost::context::detail::activation_record>'

error LNK2001: unresolved external symbol "public: static class 
boost::intrusive_ptr<struct boost::context::detail::activation_record> 
boost::context::detail::activation_record::current_rec" 
(?current_rec_at_activation_record_at_detail@context_at_boost@@2V?$intrusive_ptr_at_Uactivation_record_at_detail@context_at_boost@@@4_at_A)

I'm building with BOOST_ALL_DYN_LINK, in case that makes a difference.

Is this a known issue?  Is it fixed in a later Boost release?

(FWIW, Boost.Coroutine also generates C4251 with a different symbol but 
does not generate LNK2001, so the application still works.)