Looks like the gnulib subrepo is down. My attempts to update or clone
the Octave repo are failing with a HTTP 504 Gateway Time-out error. Is
there someone who can take a look at this?
$ hg clone https://www.octave.org/hg/octave
real URL is https://hg.savannah.gnu.org/hgweb/octave
destination directory: octave
requesting all changes
adding file changes
added 26305 changesets with 172127 changes to 13953 files (+1 heads)
new changesets 22412e3a4641:987154825e7a
updating to bookmark @
cloning subrepo gnulib from http://hg.octave.org/gnulib
abort: HTTP Error 504: Gateway Time-out
Is this still a problem for you? I just cloned Octave including the gnulib subrepo from Europe/Germany without trouble.