Re: [meta-arago][scarthgap][PATCH 09/10] libyang: Do the version bump in a yocto-check-layer compliant manner

On Thu, Nov 13, 2025 at 04:50:16PM -0600, Ryan Eatmon via lists.yoctoproject.org wrote:
> Yocto Project Compatibility requires that including a layer in a build
> not change recipes in other layers.  In this case, we were providing a
> newer version of a recipe that another layer provides.
> 
> The proper way of doing this is to create a bbappend and only change the
> minimal things needed to perform your changes.  Additionally, to pass
> the yocto-check-layer the bbappend needs to be wrapped in a manner that
> only applies your changes in the event that you are making use of your
> layer.  For Arago, that means only if we are building Arago.
> 
> Signed-off-by: Ryan Eatmon <[email protected]>
> ---
>  .../sysrepo/libyang-arago.inc                 |  9 ++++
>  .../sysrepo/libyang_%.bbappend                |  5 +++
>  .../recipes-extended/sysrepo/libyang_3.7.8.bb | 45 -------------------
>  3 files changed, 14 insertions(+), 45 deletions(-)
>  create mode 100644 meta-arago-extras/recipes-extended/sysrepo/libyang-arago.inc
>  delete mode 100644 meta-arago-extras/recipes-extended/sysrepo/libyang_3.7.8.bb
> 
> diff --git a/meta-arago-extras/recipes-extended/sysrepo/libyang-arago.inc b/meta-arago-extras/recipes-extended/sysrepo/libyang-arago.inc
> new file mode 100644
> index 00000000..b76701a8
> --- /dev/null
> +++ b/meta-arago-extras/recipes-extended/sysrepo/libyang-arago.inc
> @@ -0,0 +1,9 @@
> +PV = "3.7.8"
> +
> +LIC_FILES_CHKSUM = "file://LICENSE;md5=9bb3d334294e8719f41c531e28a9a697"
> +
> +SRCREV = "03e294d83b610f89e8ba7b2156a80dc0ad534443"
> +
> +do_install:append () {
> +    oe_multilib_header  libyang/ly_config.h
> +}

So, there's a weird problem with this change on scarthgap.

Since meta-oe/scarthgap provides an older 2.1.148 version of libyang, the 
original approach for meta-arago was to completely override the entire recipe 
with newer 3.7.8 version.

Now, for YP Compat compliance, it was converted into a .bbappend that adjusts 
the older version from meta-oe.

That older recipe in meta-oe has a multilib fix on top of standard CMake 
do_install() in the form of an :append

do_install:append () {
    oe_multilib_header  libyang/config.h
}

But the newer libyang renamed that config.h file into ly_config.h and now you 
have this code in our .bbappend

do_install:append () {
    oe_multilib_header  libyang/ly_config.h
}

But both :appends get applied and this results in the following error message:

| ERROR: libyang-3.7.8-r0 do_install: oe_multilib_header: Unable to find header libyang/config.h.

There's no easy way to disable or overwrite an existing :append, besides 
completely overriding the entire do_install() or the recipe itself...

But it appears this error is not fatal and does not seem to fail the build.


> diff --git a/meta-arago-extras/recipes-extended/sysrepo/libyang_%.bbappend b/meta-arago-extras/recipes-extended/sysrepo/libyang_%.bbappend
> index 608377e3..60d1258e 100644
> --- a/meta-arago-extras/recipes-extended/sysrepo/libyang_%.bbappend
> +++ b/meta-arago-extras/recipes-extended/sysrepo/libyang_%.bbappend
> @@ -1 +1,6 @@
> +LIBYANG_ARAGO = ""
> +LIBYANG_ARAGO:arago = "libyang-arago.inc"
> +
> +require ${LIBYANG_ARAGO}
> +
>  BBCLASSEXTEND = "native nativesdk"
> diff --git a/meta-arago-extras/recipes-extended/sysrepo/libyang_3.7.8.bb b/meta-arago-extras/recipes-extended/sysrepo/libyang_3.7.8.bb
> deleted file mode 100644
> index 3bea9bc2..00000000
> --- a/meta-arago-extras/recipes-extended/sysrepo/libyang_3.7.8.bb
> +++ /dev/null
> @@ -1,45 +0,0 @@
> -SUMMARY = "YANG data modeling language library"
> -DESCRIPTION = "libyang is a YANG data modelling language parser and toolkit written (and providing API) in C."
> -HOMEPAGE = "https://github.com/CESNET/libyang"
> -SECTION = "libs"
> -LICENSE = "BSD-3-Clause"
> -
> -LIC_FILES_CHKSUM = "file://LICENSE;md5=9bb3d334294e8719f41c531e28a9a697"
> -
> -SRCREV = "03e294d83b610f89e8ba7b2156a80dc0ad534443"
> -
> -SRC_URI = "git://github.com/CESNET/libyang.git;branch=master;protocol=https \
> -           file://0001-test_context-skip-test-case-test_searchdirs.patch \
> -           file://run-ptest \
> -           "
> -
> -S = "${WORKDIR}/git"
> -
> -# Main dependencies
> -inherit cmake pkgconfig lib_package ptest multilib_header
> -DEPENDS = "libpcre2"
> -DEPENDS += "${@bb.utils.contains('PTEST_ENABLED', '1', 'cmocka', '', d)}"
> -
> -EXTRA_OECMAKE = "-DCMAKE_BUILD_TYPE=Release"
> -EXTRA_OECMAKE += " ${@bb.utils.contains('PTEST_ENABLED', '1', '-DENABLE_TESTS=ON -DENABLE_VALGRIND_TESTS=OFF', '', d)}"
> -
> -do_compile:prepend () {
> -    if [ ${PTEST_ENABLED} = "1" ]; then
> -        sed -i -e 's|${S}|${PTEST_PATH}|g' ${B}/tests/tests_config.h
> -        sed -i -e 's|${B}|${PTEST_PATH}|g' ${B}/tests/tests_config.h
> -    fi
> -}
> -
> -do_install:append () {
> -        oe_multilib_header  libyang/ly_config.h
> -}
> -
> -do_install_ptest () {
> -    install -d ${D}${PTEST_PATH}/tests
> -    cp -f ${B}/tests/utest_* ${D}${PTEST_PATH}/tests/
> -    cp -fR ${S}/tests/modules ${D}${PTEST_PATH}/tests/
> -    install -d ${D}${PTEST_PATH}/tests/plugins
> -    cp -f ${B}/tests/plugins/plugin_*.so ${D}${PTEST_PATH}/tests/plugins/
> -}
> -
> -FILES:${PN} += "${datadir}/yang/*"
> -- 
> 2.17.1