This allows to use the board option when building as long as it has been configured before
As we don't want to force configuration of all boards each single time, auto-configuration support now has to be done per-board
Implicit dependency scanning takes significant time and, since it doesn't
produce files, it's okay to keep the resulting information across clean
commands as long as the scanner is triggered again if there's need to. This
commit accomplishes that.
The advantage of this approach can be observed by the following timings when
building the group "bin":
Method Time
------------------------------------------------------------------------
Fully clean build 5m18.633s
Clean build with scanning result persisted 4m23.346s
Clean build with ccache but non-persistent scan results 1m40.125s
Clean build with scanning results persisted and with ccache 14.843s
While at it, move management of information persisted across clean commands to
a separate module.
That makes more sense, since that module is supposed to have basic Ardupilot
specific features. The root wscript should be a mere user of those features.
That way we avoid recompiling source files that don't depend on vehicles.
Change notes:
- UTILITY_SOURCE_EXTS: moved to ap_library
- Task generators indexes: ap_library handles that now and in a better way
- Use of AP_STLIB_FEATURES: it doesn't make sense anymore, since the stlib
taskgen has empty source list
- Flags and defines: passed down to ap_library through AP_LIBRARIES_OBJECTS_KW
- Set use='mavlink' in AP_LIBRARIES_OBJECTS_KW instead of calls to
bld.ap_stlib().