kernel-yocto: replace --is-ancestor with basic git porcelain commands

--is-ancestor is a relatively new git option [commit 5907cda1, Aug 30 2012].
To support build machines with older versions of git installed, we can use
the basic porcelain commands to acheive the same check.

merge-base: "--is-ancestor A B" can be replaced with:

    if test "$(git rev-parse --verify A)" = "$(git merge-base A B)"

Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

diff --git a/meta/classes/kernel-yocto.bbclass b/meta/classes/kernel-yocto.bbclass
index ee09769d461634b7ba0089bf1d4f37988aefb6f7..929d64a2902261723328d2249371bf97937a53a5 100644 (file)
--- a/meta/classes/kernel-yocto.bbclass
+++ b/meta/classes/kernel-yocto.bbclass
@@ -131,8 +131,7 @@ do_patch() {
        # check to see if the specified SRCREV is reachable from the final branch.
        # if it wasn't something wrong has happened, and we should error.
        if [ "${machine_srcrev}" != "AUTOINC" ]; then
-               git merge-base --is-ancestor ${machine_srcrev} HEAD
-               if [ $? -ne 0 ]; then
+               if ! [ "$(git rev-parse --verify ${machine_srcrev})" = "$(git merge-base ${machine_srcrev} HEAD)" ]; then
                        bberror "SRCREV ${machine_srcrev} was specified, but is not reachable"
                        bbfatal "Check the BSP description for incorrect branch selection, or other errors."
                fi