Yes other options are needed with --justdb. Arguably,
--justdb COULD imply other options. That hasn't/wasn't
done in RPM because options and functionality can/do change,
and with the number of options present, the matrix is quite
large and unmaintainable.
There's another approach using a popt alias that is
quite simple (see "man 3 popt" or look at /usr/lib/rpm/rpmpopt*
for examples). Instead of having --foo imply --bar, then
add a --foobar popt alias that is the combination of --foo and --bar.
In this specific case, create, say, a --dorootfs popt alias which
passes --justdb --ignoresize to rpm, and change the Poky quick
start guide to use "--dorootfs".
If you chose some name spacing in option names like
--poky:rootfs
the options COULD be added to rpmpopt.in @rpm5.org rather easily as well.
I believe this problem has been corrected in the latest version by adding --ignoresize to the appropriate install calls in meta/classes/rootfs_rpm.bbclass.
If you experience this issue again, please reopen this defect.
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