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Richard Purdie
493e8b46fd
For a long time we've provided PN-PV and PN-PV-PR by tweaking PROVIDES. This looks nice at first glance however it turns out to be a bit problematic. Taking make as an example where there are two versions, 3.81 and 3.82, what should "bitbake make-3.81" do? Currently it builds make-3.81 and make-3.82 and breaks in interesting ways. Is that a bitbake bug? Well, it certainly shouldn't try and run the build. Why is it building 3.82 though? Its due to finding a dependency on "make-dev" and then trying to figure out what provides it? The answer is "make" and the default version of "make" is 3.82. So arguably, finding "make-3.81" should infer PREFERRED_VERSION_make = "3.81". Doing so resolved the above problem since now "make" resolves to "make-3.81". So what about if we have Recipe A: DEPENDS = "make-3.81" and Recipe B: DEPENDS = "make-3.82" That is clearly an error, easy. So finally what about if we have Recipe A: DEPENDS = "make-3.81" and Recipe B: DEPENDS = "make" The first recipe infers the PREFERRED_VERSION_make = "3.81" and then forces that version on everything else. Is that desired? Probably not in most cases, at least not silently. As mitigation, we could print a WARNING about this happening. The final part of the problem is that we can ony figure this out within bitbake itself. That means we'd have to teach bitbake about the PN-PV format of PROVIDES which is breaking the separation between bitbake and the metadata. We can't win :(. Nobody that I know of is using or relying on this functionality so perhaps we should just remove it instead which is what this patch does. Opinions? (From OE-Core rev: a87c205bb6cefd5e1a41b8e7ef02b5bfa380e3b6) Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Poky
====
Poky is an integration of various components to form a complete prepackaged
build system and development environment. It features support for building
customised embedded device style images. There are reference demo images
featuring a X11/Matchbox/GTK themed UI called Sato. The system supports
cross-architecture application development using QEMU emulation and a
standalone toolchain and SDK with IDE integration.
Additional information on the specifics of hardware that Poky supports
is available in README.hardware. Further hardware support can easily be added
in the form of layers which extend the systems capabilities in a modular way.
As an integration layer Poky consists of several upstream projects such as
BitBake, OpenEmbedded-Core, Yocto documentation and various sources of information
e.g. for the hardware support. Poky is in turn a component of the Yocto Project.
The Yocto Project has extensive documentation about the system including a
reference manual which can be found at:
http://yoctoproject.org/documentation
OpenEmbedded-Core is a layer containing the core metadata for current versions
of OpenEmbedded. It is distro-less (can build a functional image with
DISTRO = "") and contains only emulated machine support.
For information about OpenEmbedded, see the OpenEmbedded website:
http://www.openembedded.org/
Where to Send Patches
=====================
As Poky is an integration repository, patches against the various components
should be sent to their respective upstreams.
bitbake:
bitbake-devel@lists.openembedded.org
meta-yocto:
poky@yoctoproject.org
Most everything else should be sent to the OpenEmbedded Core mailing list. If
in doubt, check the oe-core git repository for the content you intend to modify.
Before sending, be sure the patches apply cleanly to the current oe-core git
repository.
openembedded-core@lists.openembedded.org
Note: The scripts directory should be treated with extra care as it is a mix
of oe-core and poky-specific files.