fatal error LNK1181: cannot open input file 'm.lib'

[HaoZhou0810]

Hello, I'm trying to install ois in PyCharm under windows10. Before installing ois, MSVC build tool was installed due to C++ 14.0 is required for astroalign package.
When begin to install ois, the error message shows "fatal error LNK1181: cannot open input file 'm.lib' ". I examined the LIBPATHs in error message to check whether there was a 'm.lib' file, of course this file doesn't exist.
So, is the 'm.lib' file very neccessary for ois? Is it safe to remove the line "libraries = ['m']" in setup.py like coreylynch/pyFM#18 ? Or, Is there somewhere I could find this lib file?

here is error message[I split them to make them easier to read by human :) ]

---

C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools\VC\Tools\MSVC\14.27.29110\bin\HostX86\x64\link.exe /nologo /INCREMENTAL:NO /LTCG /DLL /MANIFEST:EMBED,ID=2 /MANIFESTUAC:NO

/LIBPATH:C:\Users\zhou1\AppData\Local\Programs\Python\Python38\libs
/LIBPATH:C:\Users\zhou1\AppData\Local\Programs\Python\Python38\PCbuild\amd64
"/LIBPATH:C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools\VC\Tools\MSVC\14.27.29110\lib\x64"
"/LIBPATH:C:\Program Files (x86)\Windows Kits\10\lib\10.0.18362.0\ucrt\x64"
"/LIBPATH:C:\Program Files (x86)\Windows Kits\10\lib\10.0.18362.0\um\x64" m.lib

/EXPORT:PyInit_varconv build\temp.win-amd64-3.8\Release\src/varconv.obj build\temp.win-amd64-3.8\Release\src/oistools.obj
/OUT:build\lib.win-amd64-3.8\varconv.cp38-win_amd64.pyd
/IMPLIB:build\temp.win-amd64-3.8\Release\src\varconv.cp38-win_amd64.lib

LINK : fatal error LNK1181: cannot open input file “m.lib”
error: command 'C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools\VC\Tools\MSVC\14.27.29110\bin\HostX86\x64\link.exe' failed with exit status 1181

[martinberoiz]

Hi, yes the "m" library is supposed to translate into the flag -lm in compilers like clang and gcc. It's the (usually) built-in math library (when you include math.h). If you're compiling it on windows, I think it's safe to remove it, and it should still compile but let me know if it doesn't.

I don't know how things work on the windows side, I will open an issue for testing on windows. Thanks for pointing it out.

[HaoZhou0810]

Installation succeeded after removing libraries = ['m'], and I did some test to check ois works properly or not. It works well, thanks for your answer.

[martinberoiz]

Glad to hear it all worked well. I'll see how to incorporate this in future releases.