diff --git a/Makefile b/Makefile
index 674d656b29d00affe1f2b7c2e63f6607731a40ee..c7e8064a4033ef38a64330dff02a655a772fb141 100644
--- a/Makefile
+++ b/Makefile
@@ -77,6 +77,7 @@ edit = sed -e "s|@pkgdatadir[@]|$(DESTDIR)$(PREFIX)/share/devtools|g"
 	@m4 -P $@.in | $(edit) >$@
 	@chmod a-w "$@"
 	@chmod +x "$@"
+	@bash -O extglob -n "$@"
 
 clean:
 	rm -f $(BINPROGS) bash_completion zsh_completion