dev-manual: Added note about AUTOREV for replicating build

Feedback from Paul.

(From yocto-docs rev: ea118a9d6fa671de10b9aa8413c7d29951593ec3)

Signed-off-by: Scott Rifenbark <srifenbark@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 56 insertions, 3 deletions

diff --git a/documentation/dev-manual/dev-manual-common-tasks.xml b/documentation/dev-manual/dev-manual-common-tasks.xml
index 5f2b6ece3b..5ac8dbf737 100644
--- a/documentation/dev-manual/dev-manual-common-tasks.xml
+++ b/documentation/dev-manual/dev-manual-common-tasks.xml
@@ -6370,7 +6370,7 @@
                         Use BitBake to fetch your sources but inhibit the
                         build:
                         <literallayout class='monospaced'>
-     $ bitbake <replaceable>target</replaceable> --runonly=fetch"
+     $ bitbake <replaceable>target</replaceable> --runonly=fetch
                         </literallayout>
                         The downloads directory now has a "snapshot" of the
                         source files used for the build.
@@ -6382,6 +6382,7 @@
                         by removing any Git or other Source Control Management
                         (SCM) subdirectories such as
                         <filename>${DL_DIR}/git2/*</filename>.
+                        The tarballs already contain these subdirectories.
                         </para></listitem>
                 </orderedlist>
             </para>
@@ -6398,7 +6399,7 @@
                 downloads directory:
                 <orderedlist>
                     <listitem><para>
-                        <emphasis>Instruct the Build Process to Build Using Local Files:</emphasis>
+                        <emphasis>Using Local Files Only:</emphasis>
                         Add the
                         <ulink url='&YOCTO_DOCS_BB_URL;#var-bb-BB_NO_NETWORK'><filename>BB_NO_NETWORK</filename></ulink>
                         variables to your <filename>local.conf</filename>.
@@ -6423,10 +6424,62 @@
                         <literallayout class='monospaced'>
      $ bitbake <replaceable>target</replaceable>
                         </literallayout>
-                        The build completes using the know local "snapshot" of
+                        The build completes using the known local "snapshot" of
                         source files from your mirror.
                         The resulting tarballs for your "snapshot" of source
                         files are in the downloads directory.
+                        <note>
+                            <para>The offline build does not work if recipes
+                            attempt to find the latest version of software
+                            by setting
+                            <ulink url='&YOCTO_DOCS_REF_URL;#var-SRCREV'><filename>SRCREV</filename></ulink>
+                            to
+                            <filename>${</filename><ulink url='&YOCTO_DOCS_REF_URL;#var-AUTOREV'><filename>AUTOREV</filename></ulink><filename>}</filename>:
+                            <literallayout class='monospaced'>
+     SRCREV = "${AUTOREV}"
+                            </literallayout>
+                            When a recipe sets
+                            <filename>SRCREV</filename> to
+                            <filename>${AUTOREV}</filename>, the build system
+                            accesses the network in an attempt to determine the
+                            latest version of software from the SCM.
+                            Typically, recipes that use
+                            <filename>AUTOREV</filename> are custom or
+                            modified recipes.
+                            Recipes that reside in public repositories
+                            usually do not use <filename>AUTOREV</filename>.
+                            </para>
+
+                            <para>If you do have recipes that use
+                            <filename>AUTOREV</filename>, you can take steps to
+                            still use the recipes in an offline build.
+                            Do the following:
+                                <orderedlist>
+                                    <listitem><para>
+                                        Use a configuration generated by
+                                        enabling
+                                        <link linkend='maintaining-build-output-quality'>build history</link>.
+                                        </para></listitem>
+                                    <listitem><para>
+                                        Use the
+                                        <filename>buildhistory-collect-srcrevs</filename>
+                                        command to collect the stored
+                                        <filename>SRCREV</filename> values from
+                                        the build's history.
+                                        For more information on collecting these
+                                        values, see the
+                                        "<link linkend='build-history-package-information'>Build History Package Information</link>"
+                                        section.
+                                        </para></listitem>
+                                    <listitem><para>
+                                        Once you have the correct source
+                                        revisions, you can modify those recipes
+                                        to to set <filename>SRCREV</filename>
+                                        to specific versions of the software.
+                                        </para></listitem>
+                                </orderedlist>
+                            </para>
+                        </note>
                         </para></listitem>
                 </orderedlist>
             </para>