ref-manual: Updated the DEPENDS variable description

Fixes [YOCTO #10298]

Added a better front part description to the variable.

(From yocto-docs rev: ce8a093235aa78761fde66f345f993ab7cfac6c6)

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

1 files changed, 42 insertions, 15 deletions

diff --git a/documentation/ref-manual/ref-variables.xml b/documentation/ref-manual/ref-variables.xml
index 9d53fea0f3..99f3e03446 100644
--- a/documentation/ref-manual/ref-variables.xml
+++ b/documentation/ref-manual/ref-variables.xml
@@ -2787,28 +2787,55 @@
             <glossdef>
                 <para role="glossdeffirst">
 <!--                <para role="glossdeffirst"><imagedata fileref="figures/define-generic.png" /> -->
-                    Lists a recipe's build-time dependencies
-                    (i.e. other recipe files).
-                    The system ensures that all the dependencies listed
-                    have been built and have their contents in the appropriate
-                    sysroots before the recipe's configure task is executed.
+                    Lists a recipe's build-time dependencies.
+                    These dependencies are on other recipes whose
+                    contents (e.g. headers and shared libraries) are needed
+                    by the recipe at build time.
                 </para>
 
                 <para>
-                    Consider this simple example for two recipes named "a" and
-                    "b" that produce similarly named packages.
-                    In this example, the <filename>DEPENDS</filename>
-                    statement appears in the "a" recipe:
+                    As an example, consider a recipe <filename>foo</filename>
+                    that contains the following assignment:
                     <literallayout class='monospaced'>
-     DEPENDS = "b"
+     DEPENDS = "bar"
                     </literallayout>
-                    Here, the dependency is such that the
+                    The practical effect of the previous assignment is that
+                    all files installed by <filename>bar</filename> will be
+                    available in the appropriate staging sysroot (i.e.
+                    <link linkend='var-STAGING_DIR'><filename>STAGING_DIR*</filename></link>
+                    variables) by the time the
                     <link linkend='ref-tasks-configure'><filename>do_configure</filename></link>
-                    task for recipe "a" depends on the
+                    task for <filename>foo</filename> runs.
+                    This mechanism is implemented by having
+                    <filename>do_configure</filename> depend on the
                     <link linkend='ref-tasks-populate_sysroot'><filename>do_populate_sysroot</filename></link>
-                    task of recipe "b".
-                    This means anything that recipe "b" puts into sysroot
-                    is available when recipe "a" is configuring itself.
+                    task of each recipe listed in <filename>DEPENDS</filename>
+                    through a
+                    <filename>[</filename><ulink url='&YOCTO_DOCS_BB_URL;#variable-flags'><filename>deptask</filename></ulink><filename>]</filename>
+                    declaration in the
+                    <link linkend='ref-classes-base'><filename>base</filename></link>
+                    class.
+                    <note>
+                        It seldom is necessary to reference, for example,
+                        <filename>STAGING_DIR_HOST</filename> explicitly.
+                        The standard classes and build-related variables are
+                        configured to automatically use the appropriate staging
+                        sysroots.
+                    </note>
+                    As another example, <filename>DEPENDS</filename> can also
+                    be used to add utilities that run on the build machine
+                    during the build.
+                    For example, a recipe that makes use of a code generator
+                    built by the recipe <filename>codegen</filename> might have
+                    the following:
+                    <literallayout class='monospaced'>
+     DEPENDS = "codegen-native"
+                    </literallayout>
+                    For more information, see the
+                    <link linkend='ref-classes-native'><filename>native</filename></link>
+                    class and the
+                    <link linkend='var-EXTRANATIVEPATH'><filename>EXTRANATIVEPATH</filename></link>
+                    variable.
                     <note>
                         <title>Notes</title>
                         <itemizedlist>