migration: tweak introduction section

Ensure we have a brief introductory section and tweak the general
migration considerations a little.

(From yocto-docs rev: c94aa8b9d828f9267a70deee05bdf483dc570101)

Signed-off-by: Paul Eggleton <paul.eggleton@microsoft.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
This commit is contained in:
Paul Eggleton 2021-10-11 13:06:52 +13:00 committed by Richard Purdie
parent f0428cea44
commit 2abbaa3319

View File

@ -1,5 +1,17 @@
Introduction
============
This guide provides a list of the backwards-incompatible changes you
might need to adapt to in your existing Yocto Project configuration
when upgrading to a new release.
If you are upgrading over multiple releases, you will need to follow
the sections from the version following the one you were previously
using up to the new version you are upgrading to.
General Migration Considerations
================================
--------------------------------
Some considerations are not tied to a specific Yocto Project release.
This section presents information you should consider when migrating to
@ -26,16 +38,17 @@ any new Yocto Project release.
The better solution (where practical) is to use append files
(``*.bbappend``) to capture any customizations you want to make to a
recipe. Doing so, isolates your changes from the main recipe making
recipe. Doing so isolates your changes from the main recipe, making
them much more manageable. However, sometimes it is not practical to
use an append file. A good example of this is when introducing a
newer or older version of a recipe in another layer.
- *Updating Append Files*:
Since append files generally only contain
Since append (``.bbappend``) files generally only contain
your customizations, they often do not need to be adjusted for new
releases. However, if the ``.bbappend`` file is specific to a
releases. However, if the append file is specific to a
particular version of the recipe (i.e. its name does not use the %
wildcard) and the version of the recipe to which it is appending has
changed, then you will at a minimum need to rename the append file to
@ -50,5 +63,10 @@ any new Yocto Project release.
this is the case and assuming the patch is still needed, you must
modify the patch file so that it does apply.
.. tip::
You can list all append files used in your configuration by running:
bitbake-layers show-appends