[UPD] TODO: the 84 host binaries the chroot does not have

Measured once rather than discovered a package at a time: dpkg says what each
of the 110 apt packages ships in /usr/bin, and each of those is tested against
the chroot. Two had already been found the slow way, rsync and makeinfo, and
each cost a full build to surface.

Sorted by what it means: ten are build tools that will each block something,
eleven are documentation already settled by --auto-features auto, and eight are
not gaps at all -- bison.yacc, fakeroot-tcp, automake-1.17, ncurses6-config and
the like are Debian's alternative names for tools that are present under Arch's.
Counting those as missing would have meant building packages that exist.

--- FR ---

Mesuré une fois plutôt que découvert un paquet à la fois : dpkg dit ce que
chacun des 110 paquets apt livre dans /usr/bin, et chacun est testé contre le
chroot. Deux avaient déjà été trouvés par la voie lente, rsync et makeinfo, au
prix d'une construction complète chacun.

Classé par ce que cela signifie : dix sont des outils de construction qui
bloqueront chacun quelque chose, onze sont de la documentation déjà tranchée par
--auto-features auto, et huit ne sont pas des manques -- bison.yacc,
fakeroot-tcp, automake-1.17, ncurses6-config et compagnie sont les noms
alternatifs de Debian pour des outils présents sous ceux d'Arch. Les compter
comme absents aurait fait bâtir des paquets qui existent.

Assisted-by: Claude Opus 5

TODO.md

@@ -330,6 +330,35 @@ mistake in a smaller form. An explicit name outranks the state file, because
 being told "already built, skipping" would make the command useless for the
 one job it has.
 
+### 84 host binaries the chroot does not have — measured, not guessed
+
+`install_host_deps` installs 110 apt packages. Asking dpkg what each ships in
+`/usr/bin`, then testing every one of those against the stage-2 chroot, gives
+84 absent binaries. Worth doing once rather than discovering them a package at
+a time over a twenty-hour pass — two were found that way first (`rsync`,
+`makeinfo`) and each cost a full build to surface.
+
+Build tools, which will each block something:
+
+    gperf  help2man  po4a  xsltproc  scdoc  dtrace (systemtap)
+    cython  pyproject-build  sphinx-build  rst2man (docutils)
+
+Documentation only, and settled by `--auto-features auto`:
+
+    doxygen  asciidoctor  itstool  ducktype  yelp-build  yelp-check
+    elinks  fig2dev  transfig  rsvg-convert  clang (doxygen's)
+
+Not gaps at all, on inspection: `bison.yacc`, `fakeroot-tcp`, `faked-sysv`,
+`automake-1.17`, `aclocal-1.17`, `ncurses6-config`, `nspr-config`,
+`tcltk-depends` are Debian's alternative or versioned names for tools that are
+present under Arch's names. Counting them as missing would have sent someone
+building packages that already exist.
+
+Each is built when a package actually asks for it, not in advance — several
+carry closures much larger than themselves (`dtrace` brings systemtap,
+`sphinx-build` a Python stack), and paying for one before knowing it is needed
+is how a bootstrap doubles in size.
+
 ## Environment, not the port
 
 ### Build locale — `scripts/bootstrap-pacman.sh`