"clang++-6.0"   -fvisibility-inlines-hidden -Wno-c99-extensions -std=c++17 -stdlib=libc++ -isystem/usr/include/libcxxabi -fPIC -pthread -O0 -fno-inline -Wall -fvisibility=hidden -m64 --target=x86_64-pc-linux  -DBOOST_ALL_NO_LIB=1 -DBOOST_COBALT_USE_STD_PMR=1 -DBOOST_CONTRACT_DYN_LINK -DBOOST_CONTRACT_MAX_ARGS=0 -DBOOST_NO_CXX11_VARIADIC_TEMPLATES   -I".." -I"../libs/contract/test/public_function"  -c -o "/var/boost/run/results/boost/bin.v2/libs/contract/test/public_function-max_args0_no_tva.test/clang-linux-6.0~c++17~lc/debug/x86_64/debug-symbols-off/threading-multi/visibility-hidden/public_function/max_args0_no_tva.o" "../libs/contract/test/public_function/max_args0_no_tva.cpp"

In file included from ../libs/contract/test/public_function/max_args0_no_tva.cpp:15:
In file included from ../libs/contract/test/public_function/max_args.hpp:10:
In file included from ../boost/contract/public_function.hpp:17:
In file included from ../boost/contract/core/specify.hpp:24:
In file included from ../boost/contract/detail/condition/cond_post.hpp:15:
In file included from ../boost/contract/detail/type_traits/optional.hpp:10:
In file included from ../boost/optional.hpp:15:
In file included from ../boost/optional/optional.hpp:53:
In file included from ../boost/none.hpp:17:
../boost/none_t.hpp:24:2: error: "Boost.Optional requires some C++11 features since version 1.87. If you have an older C++ version use Boost.Optional version 1.86 or earlier."
#error "Boost.Optional requires some C++11 features since version 1.87. If you have an older C++ version use Boost.Optional version 1.86 or earlier."
 ^
In file included from ../libs/contract/test/public_function/max_args0_no_tva.cpp:15:
In file included from ../libs/contract/test/public_function/max_args.hpp:10:
In file included from ../boost/contract/public_function.hpp:32:
In file included from ../boost/contract/detail/operation/static_public_function.hpp:20:
In file included from ../boost/contract/detail/checking.hpp:13:
In file included from ../boost/thread/mutex.hpp:16:
In file included from ../boost/thread/pthread/mutex.hpp:16:
In file included from ../boost/thread/lock_types.hpp:22:
In file included from ../boost/chrono/time_point.hpp:33:
In file included from ../boost/chrono/duration.hpp:33:
In file included from ../boost/chrono/config.hpp:15:
../boost/chrono/detail/requires_cxx11.hpp:19:1: warning: C++03 support was deprecated in Boost.Chrono 1.82 and was removed in Boost.Chrono 1.84. [-W#pragma-messages]
BOOST_PRAGMA_MESSAGE("C++03 support was deprecated in Boost.Chrono 1.82 and was removed in Boost.Chrono 1.84.")
^
../boost/config/pragma_message.hpp:24:34: note: expanded from macro 'BOOST_PRAGMA_MESSAGE'
# define BOOST_PRAGMA_MESSAGE(x) _Pragma(BOOST_STRINGIZE(message(x)))
                                 ^
<scratch space>:186:2: note: expanded from here
 message("C++03 support was deprecated in Boost.Chrono 1.82 and was removed in Boost.Chrono 1.84.")
 ^
1 warning and 1 error generated.