The dependency conflicts may require a lot of time to resolve. On the contrary, uninstalling old software is easy, but it might lead to multiple broken programs and strange errors. Here is one of them, after removing the old python 3.4 and 3.5 (or whatever version it prints in your case) under Gentoo despite the rebuilding all dependencies as required by the emerge command for the new python 3.6 an error occurred trying to emerge the “app-misc/geoclue-2.5.3-r2”
[20/75] /usr/lib/python-exec/python3.6/meson --internal exe --unpickle /var/tmp/portage/app-misc/geoclue-2.5.3-r2/work/geoclue-2.5.3-build/meson-private/meson_exe_glib-mkenums_af4feac41c42ec7289410f8b20070c0528a3a7c0.dat
FAILED: public-api/gclue-enum-types.c
/usr/lib/python-exec/python3.6/meson --internal exe --unpickle /var/tmp/portage/app-misc/geoclue-2.5.3-r2/work/geoclue-2.5.3-build/meson-private/meson_exe_glib-mkenums_af4feac41c42ec7289410f8b20070c0528a3a7c0.dat
/usr/bin/env: âpython3.5â: No such file or directory
ninja: build stopped: subcommand failed.
* ERROR: app-misc/geoclue-2.5.3-r2::gentoo failed (compile phase):
* ninja -v -j15 -l14 -C /var/tmp/portage/app-misc/geoclue-2.5.3-r2/work/geoclue-2.5.3-build failed
*
* Call stack:
* ebuild.sh, line 125: Called src_compile
* environment, line 2847: Called meson_src_compile
* environment, line 1904: Called eninja '-C' '/var/tmp/portage/app-misc/geoclue-2.5.3-r2/work/geoclue-2.5.3-build'
* environment, line 1274: Called die
* The specific snippet of code:
* "$@" || die "${nonfatal_args[@]}" "${*} failed"
*
Despite the lines starting with “/usr/lib/python-exec/python3.6/meson”, there is an error for missing “python 3.5“.
Here is another example, just trying to execute the distcc-config and it immediately throws the error for missing “python 3.5“.
root@srv ~ # distcc-config /usr/bin/env: ‘python3.5’: No such file or directory
The python script distcc-config starts with:
root@srv ~ $ head /usr/bin/distcc-config
#!/usr/bin/env python3.5
# Copyright 1999-2018 Gentoo Authors
# Distributed under the terms of the GNU General Public License v2
import os, re, signal, subprocess, sys
options=[
'--get-hosts',
'--set-hosts',
'--get-verbose',
Apparently, multiple programs use this technic to explicitly put a specific version of python in the header of the python script to be used. Thus grantees the version in the header will be used even you change the system or user-preferred Python interpreter.
But uninstalling this python version all these programs will stop working till you rebuild them with emerge.
Keep on reading!