Installation on Windows

[stoprightthere]

TL;DR: Couldn't manage to just run pip install backends, had to manually modify setup.py and still found problems with building bvn_cdf extenstion.

Long story
Setup environment:
Windows 10
conda-4.9.2
gcc-10.3.0, gfortran-10.3.0 (from MSYS2)

0. Make sure gcc and gfortran are in your %PATH%.

1. First, install plum-dispatch from conda-forge:
   conda install -c conda-forge plum-dispatch

2. (In a conda env) Try to run pip install backends, it fails:

  Using cached backends-1.4.9.tar.gz (73 kB)
  Installing build dependencies ... done
  Getting requirements to build wheel ... error
  ERROR: Command errored out with exit status 1:
   command: 'd:\workplace\envs\geomgp-env\python.exe' 'd:\workplace\envs\geomgp-env\lib\site-packages\pip\_vendor\pep517\in_process\_in_process.py' get_requires_for_build_wheel 'C:\Users\mpa\AppData\Local\Temp\tmpepc7bdzf'
       cwd: C:\Users\mpa\AppData\Local\Temp\pip-install-nsrb_upj\backends_f61667fcc6d2456495c8e58501930a43
  Complete output (31 lines):
  The system cannot find the path specified.
  'which' is not recognized as an internal or external command,
  operable program or batch file.
  The system cannot find the path specified.
  'which' is not recognized as an internal or external command,
  operable program or batch file.
  The system cannot find the path specified.
  '$CC' is not recognized as an internal or external command,
  operable program or batch file.

3. Download tarball and modify setup.py so that it runs on Windows. Basically, replace which subprocess runs with shutil.which (there's no which command on Windows, it's called where). Also, replace shell=True with shell=False. See also the attached setup.py.

Also, modify setup.cfg by adding:

[build]
compiler=mingw32

4. Try running it:

> pip install .
<blah blah blah>
  d:\msys64\mingw32\bin\gcc.exe -mdll -O -Wall -DMS_WIN64 -IC:\Users\mpa\AppData\Local\Temp\pip-build-env-v1ijdp86\overlay\Lib\site-packages\numpy\core\include -Id:\workplace\envs\geomgp-env-3.7\include -Id:\workplace\envs\geomgp-env-3.7\include -c lab/bvn_cdf\bvn_cdf.c -o build\temp.win-amd64-3.7\Release\lab\bvn_cdf\bvn_cdf.o -fPIC -O2 -fopenmp
  lab/bvn_cdf\bvn_cdf.c:203:41: warning: division by zero [-Wdiv-by-zero]
    203 |     enum { __pyx_check_sizeof_voidp = 1 / (int)(SIZEOF_VOID_P == sizeof(void*)) };
        |                                         ^
  lab/bvn_cdf\bvn_cdf.c:203:12: error: enumerator value for '__pyx_check_sizeof_voidp' is not an integer constant
    203 |     enum { __pyx_check_sizeof_voidp = 1 / (int)(SIZEOF_VOID_P == sizeof(void*)) };
        |            ^~~~~~~~~~~~~~~~~~~~~~~~
<a lot of warnings>

5. This is where I gave up. I further modified setup.py so that it doesn't build the extension (this means I don't get bvn_cdf I guess) and installed lab without it.

This is an extremely inconvenient way of installing lab on Windows.

[wesselb]

Hey @stoprightthere, I’m the developer of LAB. I’m just letting you know that I’ve seen this issue and will start working on a solution.

Currently, LAB is only tested for Linux and macOS. The problem is that the installation script uses binaries not by default available on Windows. I’ll setup CI also for Windows and make sure that the installation script is Windows compatible.

[wesselb]

Hey @stoprightthere, could you try to install the latest version (pip install --upgrade backends or pip install backends==1.4.10)? I've tested this on a clean Window 10 VM within Anaconda, and LAB installed successfully.

[stoprightthere]

Hey @wesselb ! sorry for the late-ish reply. pip install backends==1.4.10 works fine. As I understand it, you dropped bvn_cdf for Windows, am I right?

Anyway marking this issue as closed.

[vdutor]

Thank you @wesselb

[stoprightthere]

Thanks a lot @wesselb!