Build errors LNK2001 on Windows [bug]

[AndreyMZ]

Steps to reproduce

1. Build and install the C library libversion on Windows:

   set LIBVERSION_REF=3.0.1
   choco install -y git cmake visualstudio2017buildtools pkgconfiglite
   git clone https://github.com/repology/libversion.git --branch="%LIBVERSION_REF%"
   cd libversion
   cmake . -G "Visual Studio 15 2017 Win64"
   cmake --build . --config Release
   cmake --install .
   setx PKG_CONFIG_PATH "C:/Program Files/libversion/lib/pkgconfig"
   

2. Check that it is discoverable by pkg-config:

   pkg-config --libs --cflags libversion
   

3. Try to build the Python module libversion:

   git clone https://github.com/repology/py-libversion.git
   cd py-libversion
   python setup.py build
   

Actual result

(venv) C:\py-libversion>pkg-config --libs --cflags libversion
-IC:/Program\ Files/libversion/include -LC:/Program\ Files/libversion/lib -lversion

(venv) C:\py-libversion>python setup.py build
running build
running build_py
running build_ext
building 'libversion._libversion' extension
C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.16.27023\bin\HostX86\x64\cl.exe /c /nologo /Ox /W3 /GL /DNDEBUG /MD "-IC:/Program Files/libversion/include" -ID:\GIT\thirdparty-tr
acking\py-libversion\venv\include -IC:\Python38\include -IC:\Python38\include "-IC:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.16.27023\ATLMFC\include" "-IC:\
Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.16.27023\include" "-IC:\Program Files (x86)\Windows Kits\NETFXSDK\4.6.1\include\um" "-IC:\Program Files (x86)\Windows Kits\10\include
\10.0.17763.0\ucrt" "-IC:\Program Files (x86)\Windows Kits\10\include\10.0.17763.0\shared" "-IC:\Program Files (x86)\Windows Kits\10\include\10.0.17763.0\um" "-IC:\Program Files (x86)\Windows Kits\10\include\1
0.0.17763.0\winrt" "-IC:\Program Files (x86)\Windows Kits\10\include\10.0.17763.0\cppwinrt" /Tcsrc/_libversion.c /Fobuild\temp.win-amd64-3.8\Release\src/_libversion.obj
_libversion.c
C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.16.27023\bin\HostX86\x64\link.exe /nologo /INCREMENTAL:NO /LTCG /DLL /MANIFEST:EMBED,ID=2 /MANIFESTUAC:NO "/LIBPATH:C:/Program Fil
es/libversion/lib" /LIBPATH:C:\py-libversion\venv\libs /LIBPATH:C:\Python38\libs /LIBPATH:C:\Python38 /LIBPATH:C:\py-libversion\venv\PCbuild\am
d64 "/LIBPATH:C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.16.27023\ATLMFC\lib\x64" "/LIBPATH:C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.16
.27023\lib\x64" "/LIBPATH:C:\Program Files (x86)\Windows Kits\NETFXSDK\4.6.1\lib\um\x64" "/LIBPATH:C:\Program Files (x86)\Windows Kits\10\lib\10.0.17763.0\ucrt\x64" "/LIBPATH:C:\Program Files (x86)\Windows Kit
s\10\lib\10.0.17763.0\um\x64" version.lib /EXPORT:PyInit__libversion build\temp.win-amd64-3.8\Release\src/_libversion.obj /OUT:build\lib.win-amd64-3.8\libversion\_libversion.cp38-win_amd64.pyd /IMPLIB:build\te
mp.win-amd64-3.8\Release\src\_libversion.cp38-win_amd64.lib
   Создается библиотека build\temp.win-amd64-3.8\Release\src\_libversion.cp38-win_amd64.lib и объект build\temp.win-amd64-3.8\Release\src\_libversion.cp38-win_amd64.exp
_libversion.obj : error LNK2001: unresolved external symbol "__imp_version_compare4"
_libversion.obj : error LNK2001: unresolved external symbol "__imp_version_compare2"
build\lib.win-amd64-3.8\libversion\_libversion.cp38-win_amd64.pyd : fatal error LNK1120: 2 unresolved externals
error: command 'C:\\Program Files (x86)\\Microsoft Visual Studio\\2017\\Community\\VC\\Tools\\MSVC\\14.16.27023\\bin\\HostX86\\x64\\link.exe' failed with exit status 1120

Expected result

No errors LNK2001:

_libversion.obj : error LNK2001: unresolved external symbol "__imp_version_compare4"
_libversion.obj : error LNK2001: unresolved external symbol "__imp_version_compare2"

Additional information

The C library libversion is installed as the following:

1. C:\Program Files\libversion\lib\libversion.lib - the import library for load-time dynamic linking of the DLL. However, the DLL itself is not installed to the system.
2. C:\Program Files\libversion\lib\version.lib - the static library.

The pkg-config file C:\Program Files\libversion\lib\pkgconfig\libversion.pc points to the second one (the static library version.lib). But it looks like only the first one (libversion.lib) contains the symbols __imp_version_compare4 and __imp_version_compare2.

[AMDmi3]

Sorry, I'm not going to work on this since I don't have Windows. Patches are welcome.

[AndreyMZ]

I will propose a PR next week.

[AMDmi3]

As I understand it's in fact problem in libversion related to incomplete installation on windows - I can move the issue there if that's correct.

And it would be nice to add test for it in appveyor along with the fix - libversion already has tests for usability of installed instance through both cmake and pkg-config, but they are not used in appveyor.

[AMDmi3]

repology/libversion#26