Commit e597257 folded $(bld_distgen) into $(src_distgen), but
neglected to update comments in .gitignore.
Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
Since subjects were added in Empire 2, we've always picked them up
from .SA requests. If you mistype a subject there, you get a "is a
NEW subject" warning, and incorrect subject pages. When building a
pristine tree, you get bogus "is a NEW subject" warnings for all
subjects. If you somehow delete the generated subjects.mk, but not
the generated subject files, the build breaks.
Declare subjects in Make variable subjects. Drop generated makefile
subject.mk.
Treat unknown topics in .SA arguments as errors. This replaces the
"$subj is a NEW subject" warning.
Treat subjects without member pages as errors. This replaces the "The
subject $subj has been removed" warning.
Safer and simpler.
We used to do all the info indexing work in info.pl: find subjects,
create subjects.mk (to tell make the list of subjects), the subject
pages, and TOP.t. Worked, but touching an info page triggered a full
rebuild of all subject pages and TOP.t.
Commit 2f14064 (v4.3.0) tried to avoid that by splitting info.pl into
findsubj.pl, mksubj.pl, mktop.pl. findsubj.pl puts not just the
subjects into subjects.mk, but also make rules for the subject pages,
to guide their remaking. mksubj.pl creates a single subject page.
mktop.pl creates TOP.t.
Unfortunately, this doesn't work so well. Since subjects.mk doesn't
exist in a virgin tree, we use -include. Unwanted consequence:
findsubj.pl failure doesn't stop make. Moreover, the complex make
machinery breaks down when info sources get removed or subjects get
dropped.
Go back to the old method, except keep mktop.pl separate, as that part
works just fine, and use simpler make rules. mksubj.pl now creates
subjects.mk and all subject pages, like info.pl did.
This effectively reverts most of commit 2f14064. I'll address the
excessive rebuilding of subject pages in a different way shortly.
