Re: how to reuse generated library in a nativesdk recipe #sdk #systemd

Martin Jansa

On Thu, Feb 20, 2020 at 08:14:04AM +0000, wrote:
On Wed, Feb 19, 2020 at 10:57:41PM +0100, Martin Jansa wrote:
DEPENDS_class-target += "systemd"
You surely meant
DEPENDS_append_class-target = " systemd"
Yes, quite likely. Tough reason why += doesn't work is a mystery to me :)

I hack things until "bitbake -e" shows the right things for the recipes.
I agree it's a bit confusing at first (I was doing the same long time
ago, before bitbake -e was even showing the history of evaluation), but
everybody who uses bitbake often should learn this simple difference:

FOO_append_override = " bar"
is "conditional" append, so it will append "bar" only when "override" is
being used

FOO_override += "bar"
always appends to "FOO_override" and then it overrides whole "FOO" variable

There are other more subtle differences like "+=" adds leading space,
_append doesn't and _append is processed later (which is important when
appending to variable set with ?=), but the above difference is a must
to know.

FOO_append += "bar"
is just silly way how to add leading space to the value, one should
always use
FOO_append = " bar"
when appending to space separated list (like DEPENDS).



On Wed, Feb 19, 2020 at 10:48 PM Mikko Rapeli <> wrote:


On Wed, Feb 19, 2020 at 01:37:19AM -0800, Armando Hernandez wrote:

I have a recipe that builds a library. The recipe specifies an
additional package "${PN}-systemd" along with other systemd related
variables and finally it instructs that the package should be built with
"-DWITH_SYSTEMD=ON" being passed to cmake. So far so good. But, I extended
this recipe to nativesdk because I need this library on it. When trying to
build the corresponding nativesdk package, the build fails at the
configuration step (i.e. "do_configure") claiming it cannot find the
package systemd.

Is there a way I can install the -already-generated libraries into my
SDK (potentially via the corresponding nativesdk recipe) without having to
rebuild the package? Or do I need to somehow include such systemd package
in my sdk (which I don't think I need at all)?

Any hints and pointers as to were to look at are very well appreciated.
Make the systemd dependency for target only, e.g. DEPENDS_class-target +=

There may be relevant use cases to build some of systemd components or
to native or nativesdk targets too. In that case add BBCLASSEXTEND +=
"nativesdk" etc
in a bbappend to systemd.

Hope this helps,


Join to automatically receive all group messages.