+OPTFILES = src/upkgopts.opt
+.opt.h:
+ $(AM_V_GEN) $(AWK) -f $(DX_BASEDIR)/scripts/gen-options.awk $< >$@.tmp
+ $(AM_V_at) mv -f $@.tmp $@
+$(OPTFILES:.opt=.h): $(DX_BASEDIR)/scripts/gen-options.awk
+MAINTAINERCLEANFILES += $(OPTFILES:.opt=.h)
+EXTRA_DIST += $(DX_BASEDIR)/scripts/gen-options.awk $(OPTFILES)
+
+# The gob rules refrain from updating unchanged headers for the convenience of
+# developers, but the headers should be distributed with up-to-date timestamps.
+dist-hook: update-headers
+update-headers: unfuck-distdir
+ for f in $(engine_GOBS:.gob=.h); do \
+ touch -c '$(distdir)'/"$$f" || exit; \
+ done
+.PHONY: update-headers
+
+# When running "make dist" in a VPATH build with a read-only srcdir, Automake
+# will produce a distribution with all files read-only. Moreover, the files
+# are read-only in distdir when the dist hooks are run. This hook will
+# manually fix up the permissions. All dist hooks that modify files in
+# distdir should list unfuck-distdir as a prerequisite.
+dist-hook: unfuck-distdir
+unfuck-distdir:
+ find '$(distdir)' -type f -exec chmod u+w {} +
+.PHONY: unfuck-distdir
+