https://svn.boost.org/trac10/ticket/13410 <p> RStudio-1.1.409_1 fails to build with clang on FreeBSD-12: </p> <pre class="wiki">/usr/ports/devel/RStudio/work/rstudio-1.1.409/src/cpp/core/system/Process.cpp In file included from /wrkdirs/usr/ports/devel/RStudio/work/rstudio-1.1.409/src/cpp/core/system/Process.cpp:16: In file included from /wrkdirs/usr/ports/devel/RStudio/work/rstudio-1.1.409/src/cpp/core/include/core/system/Process.hpp:25: In file included from /usr/local/include/boost/function.hpp:70: In file included from /usr/local/include/boost/preprocessor/iteration/detail/iter/forward1.hpp:57: In file included from /usr/local/include/boost/function/detail/function_iterate.hpp:14: In file included from /usr/local/include/boost/function/detail/maybe_include.hpp:29: /usr/local/include/boost/function/function_template.hpp:159:33: error: called object type 'nullptr_t' is not a function or function pointer BOOST_FUNCTION_RETURN((*f)(BOOST_FUNCTION_ARGS)); ^~~~ /usr/local/include/boost/function/function_template.hpp:81:36: note: expanded from macro 'BOOST_FUNCTION_RETURN' # define BOOST_FUNCTION_RETURN(X) X ^ /usr/local/include/boost/function/function_template.hpp:925:53: note: in instantiation of member function 'boost::detail::function::void_function_obj_invoker2&lt;nullptr_t, void, bool, bool&gt;::invoke' requested here { { &amp;manager_type::manage }, &amp;invoker_type::invoke }; ^ /usr/local/include/boost/function/function_template.hpp:716:13: note: in instantiation of function template specialization 'boost::function2&lt;void, bool, bool&gt;::assign_to&lt;nullptr_t&gt;' requested here this-&gt;assign_to(f); ^ /usr/local/include/boost/function/function_template.hpp:1061:5: note: in instantiation of function template specialization 'boost::function2&lt;void, bool, bool&gt;::function2&lt;nullptr_t&gt;' requested here base_type(f) ^ /usr/local/include/boost/function/function_template.hpp:1114:5: note: in instantiation of function template specialization 'boost::function&lt;void (bool, bool)&gt;::function&lt;nullptr_t&gt;' requested here self_type(f).swap(*this); ^ /wrkdirs/usr/ports/devel/RStudio/work/rstudio-1.1.409/src/cpp/core/system/Process.cpp:239:21: note: in instantiation of function template specialization 'boost::function&lt;void (bool, bool)&gt;::operator=&lt;nullptr_t&gt;' requested here cb.onHasSubprocs = NULL; ^ </pre> en-us /htdocs/site/boost.png https://svn.boost.org/trac10/ticket/13410 Trac 1.4.3 anonymous Sat, 24 Feb 2018 11:54:28 GMT