I fixed the VCS "dumb terminal" warnings on some systems by adding TERM=dumb to commit_hook.php, but this also caused some systems to hang. The change was reverted; we should find a different approach which solves the problem without the hang.
(Also reported on github), just wanted to include some more here)
Since 541664956c77 (to which we just updated) pushing to a mercurial repo hangs. It seems to be due to TERM=dumb, but I couldn't immediately find a reason.
I do have a process trace of what happens server-side, but it doesn't immediately seem useful - it's as if the server process is in a loop of some kind. See P1715. The client-side process is just waiting for a response, and doesn't seem to do anything.