migration-guides/migration-5.2.rst: add information about autotools changes

Original patch by Ross Burton:
https://lists.yoctoproject.org/g/docs/message/6466

Moved to the migration manual as it is potentially a breaking change.

Co-developed-by: Ross Burton <ross.burton@arm.com>
(From yocto-docs rev: 9b795ad8fdeadf17f08e03eedc93bc922a2d5736)

Signed-off-by: Antonin Godard <antonin.godard@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 11 insertions, 0 deletions

diff --git a/documentation/migration-guides/migration-5.2.rst b/documentation/migration-guides/migration-5.2.rst
index a5ac33d816..c4ee3fadd5 100644
--- a/documentation/migration-guides/migration-5.2.rst
+++ b/documentation/migration-guides/migration-5.2.rst
@@ -140,6 +140,17 @@ replacing is not as straightforward. For more examples, see the commit
 c++/binutils)" </openembedded-core/commit/?id=4ccc3bc8266c>` in
 :term:`OpenEmbedded-Core (OE-Core)`.
 
+:ref:`ref-classes-autotools` changes
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+-  Changes to how ``aclocal`` is invoked means that ``ACLOCALDIR`` and
+   ``ACLOCALEXTRAPATH`` are no longer used.
+
+-  Directories containing m4 files are no longer found automatically and
+   passed to ``autoreconf``. If a recipe fails to configure because it cannot
+   find m4 macros, then usually the solution is to set ``EXTRA_AUTORECONF += "-I
+   path/to/m4"`` in the recipe.
+
 Recipe changes
 ~~~~~~~~~~~~~~