id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
12969	Problem linking print_helper_t<nullptr_t> under Clang	Tony Lewis <TonyELewis@…>	Raffi Enficiaud	"I'm trying out 1.64.0 b2...

I can get the following code to compile, link and run under GCC :

{{{
#!cpp
#define BOOST_TEST_DYN_LINK

#include <boost/test/unit_test.hpp>

BOOST_AUTO_TEST_CASE( plv_tc ) {
	BOOST_TEST( nullptr == nullptr );
}

bool init_function() { return true; }
int main( int argc, char* argv[] ) {
	return ::boost::unit_test::unit_test_main( &init_function, argc, argv );
}
}}}

...with commands:

{{{
setenv BOOST_ROOT /opt/boost_1_64_0_b2_gcc_build
setenv LD_LIBRARY_PATH $BOOST_ROOT/lib
g++ -std=c++11 -isystem $BOOST_ROOT/include boost-test.nullptr-problem.cpp -L$BOOST_ROOT/lib -lboost_unit_test_framework-mt
./a.out
}}}

...but if I try with Clang:

{{{
setenv BOOST_ROOT /opt/boost_1_64_0_b2_clang_build
setenv LD_LIBRARY_PATH $BOOST_ROOT/lib
clang++ -std=c++11 -stdlib=libc++ -isystem $BOOST_ROOT/include boost-test.nullptr-problem.cpp -L$BOOST_ROOT/lib -lboost_unit_test_framework-mt
}}}

...I get:

{{{
/tmp/boost-test-fe7931.o: In function `std::__1::basic_ostream<char, std::__1::char_traits<char> >& boost::test_tools::tt_detail::operator<< <decltype(nullptr)>(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, boost::test_tools::tt_detail::print_helper_t<decltype(nullptr)> const&)':
boost-test.nullptr-problem.cpp:(.text._ZN5boost10test_tools9tt_detaillsIDnEERNSt3__113basic_ostreamIcNS3_11char_traitsIcEEEES8_RKNS1_14print_helper_tIT_EE[_ZN5boost10test_tools9tt_detaillsIDnEERNSt3__113basic_ostreamIcNS3_11char_traitsIcEEEES8_RKNS1_14print_helper_tIT_EE]+0x26): undefined reference to `boost::test_tools::tt_detail::print_log_value<decltype(nullptr)>::operator()(std::__1::basic_ostream<char, std::__1::char_traits<char> >&, decltype(nullptr))'
clang: error: linker command failed with exit code 1 (use -v to see invocation)
}}}

I may well just be doing something stupid - apologies if so.

I'm using Clang++ 3.8.1 and GCC 6.2.0 on Ubuntu 16.10 (Linux 4.8.0-46-generic; x86_64)."	Bugs	closed	Boost 1.67.0	test	Boost 1.64.0	Problem	fixed	test,link,print_helper_t,nullptr,nullptr_t,1_64_0_b2