commit: 336bf652c6faf7c15edc4cdc3076392086d6318a Author: Michał Górny <mgorny <AT> gentoo <DOT> org> AuthorDate: Wed Apr 22 19:56:49 2020 +0000 Commit: Michał Górny <mgorny <AT> gentoo <DOT> org> CommitDate: Wed Apr 22 19:57:15 2020 +0000 URL: https://gitweb.gentoo.org/data/gentoo-news.git/commit/?id=336bf652
2020-04-22-python3-7: Add news item Signed-off-by: Michał Górny <mgorny <AT> gentoo.org> 2020-04-22-python3-7/2020-04-22-python3-7.en.txt | 70 ++++++++++++++++++++++++ 1 file changed, 70 insertions(+) diff --git a/2020-04-22-python3-7/2020-04-22-python3-7.en.txt b/2020-04-22-python3-7/2020-04-22-python3-7.en.txt new file mode 100644 index 0000000..c933ca6 --- /dev/null +++ b/2020-04-22-python3-7/2020-04-22-python3-7.en.txt @@ -0,0 +1,70 @@ +Title: Python 3.7 to become the default target +Author: Michał Górny <[email protected]> +Posted: 2020-04-22 +Revision: 1 +News-Item-Format: 2.0 +Display-If-Installed: dev-lang/python:3.6 +Display-If-Installed: dev-lang/python:3.7 + +On 2020-05-06 (or later), Python 3.7 will replace Python 3.6 as one +of the default Python targets for Gentoo systems. The new default +values will be: + + PYTHON_TARGETS="python2_7 python3_7" + PYTHON_SINGLE_TARGET="python3_7" + +If you have not overriden these variables on your system, then your +package manager will switch to the new targets immediately. In order +to avoid dependency conflicts, please clean stray packages up +and rebuild/upgrade all packages with USE flag changes after the change, +e.g.: + + emerge --depclean + emerge -1vUD @world + emerge --depclean + +Please note that during the system upgrade some of the package +dependencies may temporarily become missing. While this should not +affect programs that are already fully loaded, it may cause ImportErrors +when starting Python scripts or loading additional modules (only scripts +running Python 3.6 are affected). + +In order to improve stability of the upgrade, you may choose to +temporarily enable both targets, i.e. set in /etc/portage/package.use +or its equivalent: + + */* PYTHON_TARGETS: python3_6 python3_7 + */* PYTHON_SINGLE_TARGET: -* python3_6 + +This will cause the dependencies to include both Python 3.6 and 3.7 +support whenever possible, throughout the next system upgrade. Once all +packages are updated, you can restart your scripts, remove the setting +and start another upgrade in order to cleanly remove Python 3.6. + +There are still some Gentoo packages that do not support Python 3.7. +We will be pushing updates to these packages as time permits. However, +some of them will probably be removed instead. + +If you would like to postpone the switch to Python 3.7, you can copy +the current value of PYTHON_TARGETS and/or PYTHON_SINGLE_TARGET +to /etc/portage/package.use or its equivalent: + + */* PYTHON_TARGETS: -python3_7 python3_6 + */* PYTHON_SINGLE_TARGET: -* python3_6 + +If you would like to migrate your systems earlier, you can do +the opposite. Note that if you are running ~arch, you may want to go +straight for Python 3.8 at this point. + +Please note that this switch is long overdue. Python 3.6 is no longer +receiving bug fixes. Its planned end-of-life is 2021-12-23 but we will +probably remove it earlier than that. [1] + +All above snippets assume using package.use to control USE flags. +If you still have make.conf entries for these targets, you need +to remove them. While using make.conf is possible, it is strongly +discouraged as it does not respect package defaults. The latter +can help you keep some of Python 3.6 packages without the need to +explicitly toggle flags per-package. + +[1] https://devguide.python.org/#status-of-python-branches
