lsh @2.1: destroot failure due to use of or lack of scheme compiler

[ryandesign (Ryan Carsten Schmidt)]

The build system tries to find a Scheme compiler. This might end up finding guile; if it does, it fails to build:

Making install in .
make[3]: Entering directory `/opt/local/var/macports/build/_Users_rschmidt_macports_macports-ports-svn-trunk-new_net_lsh/lsh/work/lsh-2.1/src'
/opt/local/bin/guile -l /opt/local/var/macports/build/_Users_rschmidt_macports_macports-ports-svn-trunk-new_net_lsh/lsh/work/lsh-2.1/src/scm/guile-compat.scm -e main -l /opt/local/var/macports/build/_Users_rschmidt_macports_macports-ports-svn-trunk-new_net_lsh/lsh/work/lsh-2.1/src/scm/compiler.scm \
		  -s /opt/local/var/macports/build/_Users_rschmidt_macports_macports-ports-svn-trunk-new_net_lsh/lsh/work/lsh-2.1/src/scm/gaba.scm <randomness.h >randomness.h.xT
;;; note: auto-compilation is enabled, set GUILE_AUTO_COMPILE=0
;;;       or pass the --no-auto-compile argument to disable.
;;; compiling /opt/local/var/macports/build/_Users_rschmidt_macports_macports-ports-svn-trunk-new_net_lsh/lsh/work/lsh-2.1/src/scm/guile-compat.scm
;;; /opt/local/var/macports/build/_Users_rschmidt_macports_macports-ports-svn-trunk-new_net_lsh/lsh/work/lsh-2.1/src/scm/guile-compat.scm:23:0: warning: possibly unbound variable `use-syntax'
;;; /opt/local/var/macports/build/_Users_rschmidt_macports_macports-ports-svn-trunk-new_net_lsh/lsh/work/lsh-2.1/src/scm/guile-compat.scm:23:12: warning: possibly unbound variable `ice-9'
;;; /opt/local/var/macports/build/_Users_rschmidt_macports_macports-ports-svn-trunk-new_net_lsh/lsh/work/lsh-2.1/src/scm/guile-compat.scm:23:12: warning: possibly unbound variable `syncase'
;;; compiled /opt/local/var/macports/build/_Users_rschmidt_macports_macports-ports-svn-trunk-new_net_lsh/lsh/work/.home/.cache/guile/ccache/2.2-LE-8-3.A/opt/local/var/macports/build/_Users_rschmidt_macports_macports-ports-svn-trunk-new_net_lsh/lsh/work/lsh-2.1/src/scm/guile-compat.scm.go
Backtrace:
           5 (apply-smob/1 #<catch-closure 108cbf820>)
In ice-9/boot-9.scm:
    705:2  4 (call-with-prompt _ _ #<procedure default-prompt-handler (k proc)>)
In ice-9/eval.scm:
    619:8  3 (_ #(#(#<directory (guile-user) 108480140>)))
In ice-9/boot-9.scm:
   2312:4  2 (save-module-excursion _)
  3831:12  1 (_)
In unknown file:
           0 (_)
ERROR: In procedure module-lookup: Unbound variable: use-syntax
make[3]: *** [randomness.h.x] Error 1

Or if no scheme compiler is installed, will be set to false. We can also force this outcome by using --without-scheme. In this case, it also fails to build:

Making install in .
make[3]: Entering directory `/opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_net_lsh/lsh/work/lsh-2.1/src'
false -l /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_net_lsh/lsh/work/lsh-2.1/src/scm/false-compat.scm -e main -l /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_net_lsh/lsh/work/lsh-2.1/src/scm/compiler.scm \
		  -s /opt/local/var/macports/build/_opt_bblocal_var_buildworker_ports_build_ports_net_lsh/lsh/work/lsh-2.1/src/scm/gaba.scm <randomness.h >randomness.h.xT
make[3]: *** [randomness.h.x] Error 1

The scheme compiler is only needed to regenerate files if source files are modified. We do modify many source files due to the many patchfiles that we use.

Perhaps the file being regenerated doesn't actually need to be regenerated; perhaps we could fix that by fudging the timestamps of the files we patch. Or maybe we could regenerate the file manually and include that in the patchfiles.