I was building XEmacs in the source directory on several different
machines, but discovered that I was not keeping the directories
consistent.  So I moved the sources to a network file system (Coda),
and started using --srcdir.
I have discovered that
(1) building in the source tree, I can run src/xemacs without trouble
(2) building with --srcdir=/coda/XEmacs/21.1, running src/xemacs
    from the build directory or /tmp/XEmacs/Builds/21.1/src/xemacs
    from /coda/XEmacs/21.1 gives
    bash-2.04$ /tmp/XEmacs/Builds/21.1/src/xemacs
    WARNING:
    Couldn't find obvious defaults for:
    doc-directory
    exec-directory
    lisp-directory
    Perhaps some directories don't exist, or the XEmacs executable,
    /tmp/XEmacs/Builds/21.1/src/xemacs
    is in a strange place?
(3) building with --srcdir=/coda/XEmacs/21.1, doing make install,
    and then running-in-place works fine, either cwd
This is bad, obviously.  It's going to cause hard to diagnose problems
with docstring skew a lot, and similar problems with other stuff from
those directories more rarely I would suppose.
I guess this is related to Martin's plaint about "can't move
hierarchies," but at least to me this --srcdir problem was not an
obvious consequence of Martin's observation.
-- 
University of Tsukuba                Tennodai 1-1-1 Tsukuba 305-8573 JAPAN
Institute of Policy and Planning Sciences       Tel/fax: +81 (298) 53-5091
_________________  _________________  _________________  _________________
What are those straight lines for?  "XEmacs rules."