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= Sample project ilustrating how to create configurable builds using Kconfig/Kbuild.
=
= David Corvoysier copyright Intel 2015
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The build can be configured to compile only some modules under the src directory.
The configuration rules are recursively defined in Kconfig files using the Kconfig
syntax:
https://www.kernel.org/doc/Documentation/kbuild/kconfig-language.txt
Creating the build configuration requires Kconfig's mconf and conf tools, available
for instance from the kconfig-frontends package:
http://ymorin.is-a-geek.org/projects/kconfig-frontends
Once a configuration has been defined, the build applies it using rules defined in
recursive Kbuild.mk makefiles, following the Linux kernel convention for files and
directories selection, and conditioned by the configuration:
obj-${CONFIG_FOO} += foo.o
obj-${CONFIG_BAR} += bar/
The project build tree can be extended by specifying an additional external path to
explore when parsing the configuration. At this path, the build system expects a
valid Kconfig/Kbuild.mk pair (see the example under external/sample).
Note: you need to use an absolute path.
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How to build
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Without external services:
make menuconfig
make config
make
With external services:
EXTERNAL_SERVICES=/path/to/ext make menuconfig
EXTERNAL_SERVICES=/path/to/ext make config
make
For instance:
EXTERNAL_SERVICES=$(pwd)/external/sample make menuconfig
EXTERNAL_SERVICES=$(pwd)/external/sample make config
make