Linking nghttp2 static library

Question

I want to compile a simple server app using nghtt2_asio in C++.

It compiles perfectly under shared libraries:

g++ server.cpp -O2 -std=c++20 -Wall -Wextra -lnghttp2_asio -lboost_system -lssl -lcrypto -o server

But as I compile it statically:

g++ server.cpp -static -O2 -std=c++20 -Wall -Wextra -o server -lssl -ldl -pthread -lcrypto -ldl -pthread -lnghttp2_asio -lboost_system

the linker gives me these errors:

/usr/bin/ld: /usr/local/lib/libcrypto.a(dso_dlfcn.o): in function `dlfcn_globallookup':
(.text+0x14): attenzione: Using 'dlopen' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking
/usr/bin/ld: /usr/local/lib/libcrypto.a(b_addr.o): in function `BIO_lookup_ex':
(.text+0xd0b): attenzione: Using 'getaddrinfo' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking
/usr/bin/ld: /usr/local/lib/libcrypto.a(b_sock.o): in function `BIO_gethostbyname':
(.text+0x72): attenzione: Using 'gethostbyname' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_common.o): in function `nghttp2::asio_http2::nghttp2_category_impl::message[abi:cxx11](int) const':
/home/user/Downloads/nghttp2/src/asio_common.cc:40: undefined reference to `nghttp2_strerror'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_server.o): in function `int nghttp2::asio_http2::server::http2_handler::on_read<8192ul>(boost::array<unsigned char, 8192ul> const&, unsigned long)':
/home/user/Downloads/nghttp2/src/asio_server_http2_handler.h:103: undefined reference to `nghttp2_session_mem_recv'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_server.o): in function `boost::asio::ssl::detail::engine::engine(ssl_ctx_st*)':
/usr/include/boost/asio/ssl/detail/impl/engine.ipp:55: undefined reference to `BIO_new_bio_pair'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_server.o): in function `int nghttp2::asio_http2::server::http2_handler::on_write<65536ul>(boost::array<unsigned char, 65536ul>&, unsigned long&)':
/home/user/Downloads/nghttp2/src/asio_server_http2_handler.h:129: undefined reference to `nghttp2_session_mem_send'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_server.o): in function `int nghttp2::asio_http2::server::http2_handler::on_read<8192ul>(boost::array<unsigned char, 8192ul> const&, unsigned long)':
/home/user/Downloads/nghttp2/src/asio_server_http2_handler.h:103: undefined reference to `nghttp2_session_mem_recv'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_server.o): in function `int nghttp2::asio_http2::server::http2_handler::on_write<65536ul>(boost::array<unsigned char, 65536ul>&, unsigned long&)':
/home/user/Downloads/nghttp2/src/asio_server_http2_handler.h:129: undefined reference to `nghttp2_session_mem_send'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_server.o): in function `int nghttp2::asio_http2::server::http2_handler::on_read<8192ul>(boost::array<unsigned char, 8192ul> const&, unsigned long)':
/home/user/Downloads/nghttp2/src/asio_server_http2_handler.h:103: undefined reference to `nghttp2_session_mem_recv'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_server_http2_handler.o): in function `nghttp2::asio_http2::server::(anonymous namespace)::on_frame_not_send_callback(nghttp2_session*, nghttp2_frame const*, int, void*)':
/home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:230: undefined reference to `nghttp2_submit_rst_stream'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_server_http2_handler.o): in function `nghttp2::asio_http2::server::http2_handler::~http2_handler()':
/home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:258: undefined reference to `nghttp2_session_del'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_server_http2_handler.o): in function `nghttp2::asio_http2::server::http2_handler::start()':
/home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:274: undefined reference to `nghttp2_session_callbacks_new'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_server_http2_handler.o): in function `std::_Bind<void (*(nghttp2_session_callbacks*))(nghttp2_session_callbacks*)>::_Bind(std::_Bind<void (*(nghttp2_session_callbacks*))(nghttp2_session_callbacks*)>&&)':
/usr/include/c++/11.1.0/functional:494: undefined reference to `nghttp2_session_callbacks_del'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_server_http2_handler.o): in function `nghttp2::asio_http2::server::http2_handler::start()':
/home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:281: undefined reference to `nghttp2_session_callbacks_set_on_begin_headers_callback'
/usr/bin/ld: /home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:283: undefined reference to `nghttp2_session_callbacks_set_on_header_callback'
/usr/bin/ld: /home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:285: undefined reference to `nghttp2_session_callbacks_set_on_frame_recv_callback'
/usr/bin/ld: /home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:287: undefined reference to `nghttp2_session_callbacks_set_on_data_chunk_recv_callback'
/usr/bin/ld: /home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:289: undefined reference to `nghttp2_session_callbacks_set_on_stream_close_callback'
/usr/bin/ld: /home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:291: undefined reference to `nghttp2_session_callbacks_set_on_frame_send_callback'
/usr/bin/ld: /home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:293: undefined reference to `nghttp2_session_callbacks_set_on_frame_not_send_callback'
/usr/bin/ld: /home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:296: undefined reference to `nghttp2_session_server_new'
/usr/bin/ld: /home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:302: undefined reference to `nghttp2_submit_settings'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_server_http2_handler.o): in function `nghttp2::asio_http2::server::http2_handler::should_stop() const':
/home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:333: undefined reference to `nghttp2_session_want_read'
/usr/bin/ld: /home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:334: undefined reference to `nghttp2_session_want_write'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_server_http2_handler.o): in function `nghttp2::asio_http2::server::http2_handler::stream_error(int, unsigned int)':
/home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:47: undefined reference to `nghttp2_submit_rst_stream'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_server_http2_handler.o): in function `nghttp2::asio_http2::server::http2_handler::resume(nghttp2::asio_http2::server::stream&)':
/home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:428: undefined reference to `nghttp2_session_resume_data'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_server_http2_handler.o): in function `nghttp2::asio_http2::server::(anonymous namespace)::on_header_callback(nghttp2_session*, nghttp2_frame const*, unsigned char const*, unsigned long, unsigned char const*, unsigned long, unsigned char, void*)':
/home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:109: undefined reference to `nghttp2_submit_rst_stream'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_server_http2_handler.o): in function `nghttp2::asio_http2::server::http2_handler::submit_trailer(nghttp2::asio_http2::server::stream&, std::multimap<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, nghttp2::asio_http2::header_value, std::less<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, nghttp2::asio_http2::header_value> > >)':
/home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:387: undefined reference to `nghttp2_submit_trailer'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_server_http2_handler.o): in function `nghttp2::asio_http2::server::http2_handler::start_response(nghttp2::asio_http2::server::stream&)':
/home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:366: undefined reference to `nghttp2_submit_response'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-asio_server_http2_handler.o): in function `nghttp2::asio_http2::server::http2_handler::push_promise(boost::system::error_code&, nghttp2::asio_http2::server::stream&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::multimap<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, nghttp2::asio_http2::header_value, std::less<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const, nghttp2::asio_http2::header_value> > >)':
/home/user/Downloads/nghttp2/src/asio_server_http2_handler.cc:454: undefined reference to `nghttp2_submit_push_promise'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-http2.o): in function `nghttp2::http2::determine_window_update_transmission(nghttp2_session*, int)':
/home/user/Downloads/nghttp2/src/http2.cc:577: undefined reference to `nghttp2_session_get_effective_recv_data_length'
/usr/bin/ld: /home/user/Downloads/nghttp2/src/http2.cc:578: undefined reference to `nghttp2_session_get_effective_local_window_size'
/usr/bin/ld: /home/user/Downloads/nghttp2/src/http2.cc:580: undefined reference to `nghttp2_session_get_stream_effective_recv_data_length'
/usr/bin/ld: /home/user/Downloads/nghttp2/src/http2.cc:582: undefined reference to `nghttp2_session_get_stream_effective_local_window_size'
/usr/bin/ld: /usr/local/lib/libnghttp2_asio.a(libnghttp2_asio_la-http2.o): in function `nghttp2::http2::check_nv(unsigned char const*, unsigned long, unsigned char const*, unsigned long)':
/home/user/Downloads/nghttp2/src/http2.cc:698: undefined reference to `nghttp2_check_header_name'
/usr/bin/ld: /home/user/Downloads/nghttp2/src/http2.cc:701: undefined reference to `nghttp2_check_header_value'
collect2: error: ld returned 1 exit status

Can someone explain me what happens?

Answer 1

Can someone explain me what happens?

There are several problems here.

1. You have unresolved symbols. As nm said in a comment, you need to add -libnghttp2 .

2. Your order of libraries on the link line is wrong. Lower-level libraries should follow higher-level libraries on the link line. The right order is something like:

-lnghttp2_asio -libnghttp2 -lboost_system -lssl -lcrypto -ldl

See this blog post for explanation.

3. You are linking a fully-static binary.

Contrary to popular belief, such binaries (at least on Linux) are significantly less portable than dynamically linked ones.

What the warning is telling you is that IF you try to run this binary on a system that has a different version of GLIBC installed (could be a different system from the one you built on, or even the same system but after an upgrade to a different version of GLIBC), then your binary may crash (and very likely will crash).

You will be much better off not doing a fully-static link.

Note: you don't have to link against libnghttp2_asio etc. dynamically, just against the libc and libdl and libcrypto .