title: g++ libcurl static build fails on nghttp2 library
body: <p>I have an application which uses the LibCurl library in combination with the nghttp2-library which I would like to statically link.</p>
  
  <p>The build command I use to build:</p>
  
  <pre><code>i686-w64-mingw32-g++ -Wall Programm.cpp -o Programm.exe -I/opt/mingw64/Win32/include -L/opt/mingw64/Win32/lib -I/Software -I/Software/Deps -std=c++11 -lgcc -lstdc++ -lnghttp2 -lcurl -lssl -lcrypto -DCURL_STATICLIB -lpthread -lws2_32 -static
  </code></pre>
  
  <p>The build-errors it produces:</p>
  
  <pre><code>/opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x47): undefined reference to `_imp__nghttp2_session_get_stream_user_data'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x77): undefined reference to `_imp__nghttp2_session_get_stream_user_data'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0xaf): undefined reference to `_imp__nghttp2_session_get_stream_user_data'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x448): undefined reference to `_imp__nghttp2_session_get_stream_user_data'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x4ac): undefined reference to `_imp__nghttp2_session_get_stream_user_data'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x5d4): more undefined references to `_imp__nghttp2_session_get_stream_user_data' follow
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x6ee): undefined reference to `_imp__nghttp2_session_want_write'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x75e): undefined reference to `_imp__nghttp2_priority_spec_init'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x7e2): undefined reference to `_imp__nghttp2_submit_priority'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x7ef): undefined reference to `_imp__nghttp2_session_send'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x8d3): undefined reference to `_imp__nghttp2_session_del'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x94d): undefined reference to `_imp__nghttp2_session_get_stream_user_data'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0xb43): undefined reference to `_imp__nghttp2_submit_rst_stream'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0xb4e): undefined reference to `_imp__nghttp2_is_fatal'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0xb69): undefined reference to `_imp__nghttp2_session_get_remote_settings'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0xcdb): undefined reference to `_imp__nghttp2_submit_rst_stream'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0xce4): undefined reference to `_imp__nghttp2_is_fatal'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0xda8): undefined reference to `_imp__nghttp2_session_set_stream_user_data'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0xe80): undefined reference to `_imp__nghttp2_session_get_stream_user_data'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0xeca): undefined reference to `_imp__nghttp2_session_set_stream_user_data'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0xf6d): undefined reference to `_imp__nghttp2_session_want_read'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0xf87): undefined reference to `_imp__nghttp2_session_want_write'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0xfc7): undefined reference to `_imp__nghttp2_session_mem_recv'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x1036): undefined reference to `_imp__nghttp2_strerror'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x11c5): undefined reference to `_imp__nghttp2_http2_strerror'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x1298): undefined reference to `_imp__nghttp2_session_resume_data'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x12ca): undefined reference to `_imp__nghttp2_is_fatal'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x176c): undefined reference to `_imp__nghttp2_submit_request'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x17bb): undefined reference to `_imp__nghttp2_session_send'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x17f9): undefined reference to `_imp__nghttp2_session_resume_data'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x1d0c): undefined reference to `_imp__nghttp2_session_mem_recv'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x1d19): undefined reference to `_imp__nghttp2_is_fatal'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x1f9e): undefined reference to `_imp__nghttp2_strerror'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2037): undefined reference to `_imp__nghttp2_session_callbacks_new'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2071): undefined reference to `_imp__nghttp2_session_callbacks_set_send_callback'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2086): undefined reference to `_imp__nghttp2_session_callbacks_set_on_frame_recv_callback'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x209b): undefined reference to `_imp__nghttp2_session_callbacks_set_on_invalid_frame_recv_callback'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x20b0): undefined reference to `_imp__nghttp2_session_callbacks_set_on_data_chunk_recv_callback'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x20c5): undefined reference to `_imp__nghttp2_session_callbacks_set_before_frame_send_callback'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x20da): undefined reference to `_imp__nghttp2_session_callbacks_set_on_frame_send_callback'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x20ef): undefined reference to `_imp__nghttp2_session_callbacks_set_on_frame_not_send_callback'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2104): undefined reference to `_imp__nghttp2_session_callbacks_set_on_stream_close_callback'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2119): undefined reference to `_imp__nghttp2_session_callbacks_set_on_begin_headers_callback'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x212e): undefined reference to `_imp__nghttp2_session_callbacks_set_on_header_callback'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2143): undefined reference to `_imp__nghttp2_session_callbacks_set_error_callback'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x215e): undefined reference to `_imp__nghttp2_session_client_new'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x216d): undefined reference to `_imp__nghttp2_session_callbacks_del'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x21b7): undefined reference to `_imp__nghttp2_session_get_stream_user_data'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x21e7): undefined reference to `_imp__nghttp2_session_get_stream_user_data'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x22bc): undefined reference to `_imp__nghttp2_version'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x22f2): undefined reference to `_imp__nghttp2_http2_strerror'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2510): undefined reference to `_imp__nghttp2_session_set_stream_user_data'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2555): undefined reference to `_imp__nghttp2_submit_rst_stream'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2631): undefined reference to `_imp__nghttp2_pack_settings_payload'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2751): undefined reference to `_imp__nghttp2_session_resume_data'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x298c): undefined reference to `_imp__nghttp2_submit_settings'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x29bd): undefined reference to `_imp__nghttp2_session_set_local_window_size'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2a41): undefined reference to `_imp__nghttp2_session_upgrade'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2a54): undefined reference to `_imp__nghttp2_strerror'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2a85): undefined reference to `_imp__nghttp2_strerror'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2ab5): undefined reference to `_imp__nghttp2_strerror'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2afb): undefined reference to `_imp__nghttp2_session_set_stream_user_data'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2b49): undefined reference to `_imp__nghttp2_session_mem_recv'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2b54): undefined reference to `_imp__nghttp2_is_fatal'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2b88): undefined reference to `_imp__nghttp2_strerror'
  /opt/mingw64/Win32/lib/libcurl.a(libcurl_la-http2.o):http2.c:(.text+0x2bb5): undefined reference to `_imp__nghttp2_strerror'
  collect2: error: ld returned 1 exit status
  </code></pre>
  
  <p>I have built nghttp2 with the following commands:</p>
  
  <pre><code>wget https://github.com/nghttp2/nghttp2/releases/download/v1.27.0/nghttp2-1.27.0.tar.gz
  tar xf nghttp2-1.27.0.tar.gz
  cd nghttp2-1.27.0/
  ./configure --host=i686-w64-mingw32 --prefix=/opt/mingw64/Win32
  make
  make install
  </code></pre>
  
  <p>So, what is wrong with the build command looking at static linking LibCurl with the nghttp2 library?</p>