Reputation: 908
I am having trouble understanding bitbake
recipes. Can you please help me understand the difference between RDEPENDS
and DEPENDS
?
I read the reference and I know that they stand for runtime dependency and build dependency respectively, but what is the effect on it in a bitbake
recipe?
As far as I understand, if a package A
DEPENDS
on another B
, B
has to be built and ready to enable A
to build. I assume, bitbake
isn't related to the runtime, it's only there for building and deploying the packages. So what is the difference?
Upvotes: 29
Views: 16606
Reputation: 61575
As you say, bitbake is concerned with building and deploying the packages, and it needs to deploy all the packages that are needed to satisfy runtime dependencies on the target system.
If your recipe says that target T DEPENDS
on a target P, that tells
bitbake that it must build P before T, because T can't be
built without P.
If your recipe says that T RDEPENDS
on P, that tells
bitbake that it must deploy P to the target system if it
deploys T, because T can't be used without P.
For example, you can't build tar
without the C compiler, but
you don't need the C compiler to use tar
. You can deploy tar
without deploying the C compiler. So that's a DEPEND
.
On the other hand, you can't use tar
without the runtime C library.
If tar
is deployed, the runtime C library must also be deployed.
So that's an RDEPEND
.
The bitake technicalities are:
If T DEPENDS
on P then T's do_configure
task is made to depend
on P's do_populate_sysroot
task.
If T RDEPENDS
on P then T's do_build
task ia made to depend on P's
do_package_write
task.
Upvotes: 68