kconfig/cmake: Improve reconfiguration behavior
There are some issues with the behavior when rerunning CMake in an
already initialized build directory:
1. The check for assignments to promptless symbols in configuration
fragments isn't run when reconfiguring, because it only runs if
zephyr/.config doesn't exist
2. As outlined in
https://github.com/zephyrproject-rtos/zephyr/issues/9573, you can
get into situations where zephyr/.config is invalid (e.g. due to
being outdated), but menuconfig/guiconfig can't be run to fix it
3. If kconfig.py fails while merging fragments during reconfiguration,
it will ignore the fragments during the next reconfiguration and use
the existing zephyr/.config instead, because the fragment checksum
is calculated and saved before running kconfig.py
(Footnote: The input configuration file(s) to kconfig.py can be either a
list of configuration fragments, when merging fragments, or just
zephyr/.config, if the merged configuration is up-to-date. The output
configuration file is always zephyr/.config.)
To fix the first two issues, explicitly tell kconfig.py when it's
dealing with handwritten configuration input (fragments), via a new
--handwritten-input-configs flag. This is more robust than checking
whether zephyr/.config exists, which was the old logic.
When dealing with handwritten input, there should be no assignments to
promptless symbols. Assignments to promptless symbols is expected in
zephyr/.config however, because it doubles as configuration output.
When running menuconfig/guiconfig, the input configuration is
zephyr/.config rather than configuration fragments, so this change also
makes sure that menuconfig can always be run as long as zephyr/.config
exists and is up-to-date.
To fix the last issue, only write the checksum for the configuration
fragments if kconfig.py succeeds (which means it wrote a
zephyr/.config).
Also improve naming a bit, add help texts for the command-line
parameters to kconfig.py, and simplify write_kconfig_filenames() by
moving logic into it.
Partial fix for
https://github.com/zephyrproject-rtos/zephyr/issues/9573, without the
part in #issuecomment-469701831. Can still run into issues when e.g.
when CMake files can't make sense of settings.
Signed-off-by: Ulf Magnusson <Ulf.Magnusson@nordicsemi.no>
2 files changed
