I can build Go from tip on Plan 9 using a local repo clone.  I want
to  build it using a repo exported from a Linux box (via u9fs) -- because
of codereview extensions and keeping a consistent repo.  Trying to build a
remotely mounted clone, I get:

cpue% ./all.rc
# Building C bootstrap tool.
cmd/dist

# Building compilers and Go bootstrap tool for host, plan9/386.
*** failed to import extension codereview from
$GOROOT/lib/codereview/codereview.py: [Errno 12] Invalid argument
abort: There is no Mercurial repository here (.hg not found)

go tool dist: FAILED: /bin/hg identify -b:
'/n/zotac/usr/local/go/VERSION.cache' does not exist
cpue%

/n/zotac is the Linux filesystem that is served by u9fs. Any hints?

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