This takes a list of properties and generate finish arguments.
Additionally you can specify "bundle": true, which causes f-b to emit
an actual extension implementation, similar to e.g. the locale
and debuginfo extension.
For example, add $(AM_CFLAGS) to mumble_CFLAGS. Since $(WARN_CFLAGS) is
only added to $(AM_CFLAGS), this fixes the lack of inclusion of the
compiler warning flags in the compilation of half of flatpak.
Note that $(AM_*) variables are only used by automake if a more specific
(per-target) special variable is not defined instead. So if you define
mumble_CFLAGS, AM_CFLAGS will not be used for that target unless
explicitly included in mumble_CFLAGS.
See
https://www.gnu.org/software/automake/manual/html_node/Flag-Variables-Ordering.html.
Do the same for $(AM_LIBADD), $(AM_LDFLAGS), etc. These are not
currently defined, but it’s good practice to include them in
mumble_LIBADD (etc.) just in case they’re defined in future. Hopefully
their inclusions will be cargo-culted to any new targets which are
added, retaining full coverage of the code base.
Signed-off-by: Philip Withnall <withnall@endlessm.com>