Fix Lintian warning: debian-rules-ignores-make-clean-error

diff --git a/debian/rules b/debian/rules
index cb8223a4c7202a9ed7fdf29e1461d6a90652833b..75e06aa4766ee46911da9101a226f6d99dda49e7 100755 (executable)
--- a/debian/rules
+++ b/debian/rules
@@ -133,8 +133,7 @@ override_dh_auto_install-indep: override_dh_auto_install-arch debian/guile.reloc
 ## we need to nuke the parser files, because if there is a mismatch
 ## between upstreams bison and our bison, the build will fail epically
 override_dh_auto_clean:
-       rm -rf no-trespassing
-       -$(MAKE) -C guile18 maintainer-clean
+       [ ! -f guile18/Makefile ] || $(MAKE) -C guile18 maintainer-clean
        rm -f lily/out/parser.*
        dh_auto_clean --no-parallel