Windows bootstrap fails with Python 3.7.1

Submitted by Jos van Egmond

Description

Git master on Windows with Python 3.7.1 running: python ./cerbero-uninstalled bootstrap

The following error is printed:

[(12/16) meson -> configure ]
[(12/16) meson -> compile ]
[(12/16) meson -> install ]
running install
Checking .pth file support in c:\gstreamer\build\cerbero\build\build-tools\Lib\site-packages\
c:\python3\pythonw.exe -E -c pass
TEST FAILED: c:\gstreamer\build\cerbero\build\build-tools\Lib\site-packages\ does NOT support .pth files
error: bad install directory or PYTHONPATH

You are attempting to install a package to a directory that is not
on PYTHONPATH and which Python does not read ".pth" files from. The
installation directory you specified (via --install-dir, --prefix, or
the distutils default setting) was:

c:\gstreamer\build\cerbero\build\build-tools\Lib\site-packages\

and your PYTHONPATH environment variable currently contains:

'c:/gstreamer/build/cerbero/build/build-tools/Lib/site-packages;c:/gstreamer/build/cerbero/build/build-tools/Lib/site-packages'

Here are some of your options for correcting the problem:

You can choose a different installation directory, i.e., one that is
on PYTHONPATH or supports .pth files
You can add the installation directory to the PYTHONPATH environment
variable. (It must then also be on PYTHONPATH whenever you run
Python and want to use the package(s) you are installing.)
You can set up the installation directory to support ".pth" files by
using one of the approaches described here:

https://setuptools.readthedocs.io/en/latest/easy_install.html#custom-installation-locations

Please make the appropriate changes for your system and try again.
Recipe 'meson' failed at the build step 'install'
Traceback (most recent call last):
File ".\cerbero\build\oven.py", line 144, in _cook_recipe
stepfunc()
File "c:/gstreamer/build/cerbero/recipes/build-tools/meson.recipe", line 36, in install
cwd=self.build_dir)
File "c:\python3\lib\subprocess.py", line 341, in check_call
raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['c:\python3\python.exe', 'setup.py', 'install', '--prefix', 'c:\gstreamer\build\cerbero\build\build-tools']' returned non-zero exit status 1.
Select an action to proceed:
[0] Enter the shell
[1] Rebuild the recipe from scratch
[2] Rebuild starting from the failed step
[3] Skip recipe
[4] Abort

Downgrading Python to 3.5.4 has solved it. Have tried many workarounds but downgrade was more straightforward. Haven't tried Python 3.6.x.