71: Why do I get "Process shell exited abnormally with code 1"?
The most likely reason for this message is that the "env" program is not
properly installed. Compile this program for your architecture, and
install it with a+x permission in the architecture-dependent Emacs
program directory. (You can find what this directory is at your site by
inspecting the value of the variable exec-directory by typing "C-h v
exec-directory RET".)
You should also check for other programs named "env" in your path (e.g.,
SunOS has a program named /usr/bin/env). We don't understand why this
can cause a failure and don't know a general solution for working around
the problem in this case.
The "make clean" command will remove "env" and other vital programs, so
be careful when using it.
It has been reported that this sometimes happened when Emacs was started
as an X client from an xterm window (i.e., had a controlling tty) but the
xterm was later terminated.
See also PROBLEMS (in the top-level directory when you unpack the Emacs
source) for other possible causes of this message.