diff --git a/ChangeLog b/ChangeLog
index ae85ada978..8aef6ede7e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Thu Jun 25 14:14:16 2015  takiy33  <takiy33@gmail.com>
+
+	* test/test_prime.rb (test_eratosthenes_works_fine_after_timeout):
+	  use spaces instead of TABs in ruby codes.  [Fix GH-944]
+
 Thu Jun 25 07:08:35 2015  Koichi Sasada  <ko1@atdot.net>
 
 	* gc.c (obj_info, method_type_name): show method type name in a string
diff --git a/test/test_prime.rb b/test/test_prime.rb
index 75d83a5b85..f6440f861b 100644
--- a/test/test_prime.rb
+++ b/test/test_prime.rb
@@ -180,8 +180,8 @@ class TestPrime < Test::Unit::TestCase
       end
 
       begin
-	Timeout.timeout(0.5) { Prime.each(7*37){} }
-	flunk("timeout expected")
+        Timeout.timeout(0.5) { Prime.each(7*37){} }
+        flunk("timeout expected")
       rescue Timeout::Error
       end
     ensure