common.mk: disable force download of unicode files by default

* tool/downloader.rb: add -a option to always download regardless
  existing files.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@48058 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,8 @@
+Mon Oct 20 23:58:04 2014  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* tool/downloader.rb: add -a option to always download regardless
+	  existing files.
+
 Mon Oct 20 23:18:18 2014  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 	* lib/mkmf.rb: no need to convert path separator for COPY because it's

common.mk

@@ -1089,10 +1089,12 @@ update-gems: PHONY
 	    -e 'Downloader::RubyGems.download(gem)' \
 	    bundled_gems
 
+# ALWAYS_UPDATE_UNICODE = yes
+
 update-unicode: PHONY
 	$(ECHO) Downloading Unicode data files...
 	$(Q) $(BASERUBY) -C "$(srcdir)/enc/unicode/data" \
-	    ../../../tool/downloader.rb unicode \
+	    ../../../tool/downloader.rb -e $(ALWAYS_UPDATE_UNICODE:yes=-a) unicode \
 	    UnicodeData.txt CompositionExclusions.txt NormalizationTest.txt
 
 enc/unicode/data/UnicodeData.txt \

tool/downloader.rb

@@ -113,6 +113,8 @@ if $0 == __FILE__
       ARGV.shift
     when '-e'
       ims = nil
+    when '-a'
+      ims = true
     when /\A-/
       abort "#{$0}: unknown option #{ARGV[0]}"
     else