pkg.mk in zbatery-3.4.0 vs pkg.mk in zbatery-4.0.0

@@ -67,11 +67,11 @@
 	-find lib -type f -name '*.rbc' -exec rm -f '{}' ';'
 	-find ext -type f -name '*.rbc' -exec rm -f '{}' ';'
 	$(RM) -r doc
 	$(WRONGDOC) all
 	install -m644 COPYING doc/COPYING
-	install -m644 $(shell grep '^[A-Z]' .document) doc/
+	install -m644 $(shell LC_ALL=C grep '^[A-Z]' .document) doc/
 
 ifneq ($(VERSION),)
 pkggem := pkg/$(rfpackage)-$(VERSION).gem
 pkgtgz := pkg/$(rfpackage)-$(VERSION).tgz
 release_notes := release_notes-$(VERSION)
@@ -165,7 +165,11 @@
 # "gzip_static on" can serve the gzipped versions directly.
 doc_gz: docs = $(shell find doc -type f ! -regex '^.*\.\(gif\|jpg\|png\|gz\)$$')
 doc_gz:
 	for i in $(docs); do \
 	  gzip --rsyncable -9 < $$i > $$i.gz; touch -r $$i $$i.gz; done
+check-warnings:
+	@(for i in $$(git ls-files '*.rb'| grep -v '^setup\.rb$$'); \
+	  do $(RUBY) -d -W2 -c $$i; done) | grep -v '^Syntax OK$$' || :
 
 .PHONY: all .FORCE-GIT-VERSION-FILE doc test $(test_units) manifest
+.PHONY: check-warnings