diff --git a/ChangeLog b/ChangeLog
index c3aa69ad2d..91ed884668 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Tue Aug 16 21:04:30 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* common.mk (UNICODE_HDR_DIR): separate unicode header files from
+	  unicode data files.  [ruby-core:76879] [Bug #12677]
+
 Tue Aug 16 11:17:51 2016  Koichi ITO  <koic.ito@gmail.com>
 
 	* lib/net/http/header.rb: Fix typo. [ci skip][fix GH-1407]
diff --git a/common.mk b/common.mk
index 0785b6edb5..ae29c4c83c 100644
--- a/common.mk
+++ b/common.mk
@@ -18,7 +18,7 @@ UNICODE_VERSION = 8.0.0
 # ALWAYS_UPDATE_UNICODE = yes
 UNICODE_DATA_DIR = enc/unicode/data/$(UNICODE_VERSION)
 UNICODE_SRC_DATA_DIR = $(srcdir)/$(UNICODE_DATA_DIR)
-UNICODE_HDR_DIR = $(UNICODE_SRC_DATA_DIR)
+UNICODE_HDR_DIR = $(srcdir)/enc/unicode/$(UNICODE_VERSION)
 UNICODE_DATA_HEADERS = \
 	$(UNICODE_HDR_DIR)/casefold.h \
 	$(UNICODE_HDR_DIR)/name2ctype.h \
diff --git a/enc/unicode/data/8.0.0/casefold.h b/enc/unicode/8.0.0/casefold.h
similarity index 100%
rename from enc/unicode/data/8.0.0/casefold.h
rename to enc/unicode/8.0.0/casefold.h
diff --git a/enc/unicode/data/8.0.0/name2ctype.h b/enc/unicode/8.0.0/name2ctype.h
similarity index 100%
rename from enc/unicode/data/8.0.0/name2ctype.h
rename to enc/unicode/8.0.0/name2ctype.h
diff --git a/tool/make-snapshot b/tool/make-snapshot
index 36a83ad658..73278a34bc 100755
--- a/tool/make-snapshot
+++ b/tool/make-snapshot
@@ -326,10 +326,6 @@ update-gems:
         f.puts mk
       end
       system("make", "prereq", *args.map {|arg| arg.join("=")})
-      Dir.glob("enc/unicode/data/*/*.h") do |f|
-        FileUtils::Verbose.mkpath("."+File.dirname(f[12..-1]))
-        FileUtils::Verbose.mv(f, "."+f[12..-1])
-      end
       clean.push("rbconfig.rb", ".rbconfig.time", "enc.mk")
       print "prerequisites"
     else
@@ -338,9 +334,6 @@ update-gems:
     vcs.after_export(".") if exported
     FileUtils.rm_rf(clean) unless $keep_temp
     FileUtils.rm_rf(".downloaded-cache")
-    if File.directory?(".data")
-      FileUtils.mv(".data", "enc/unicode/data")
-    end
     if File.exist?("gems/bundled_gems")
       gems = Dir.glob("gems/*.gem")
       gems -= File.readlines("gems/bundled_gems").map {|line|