diff --git a/ChangeLog b/ChangeLog
index 2227df2a95..22d93caf1a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Thu Jun 20 05:08:53 2013  Koichi Sasada  <ko1@atdot.net>
+
+	* gc.c (gc_marks): fix wrong option. FALSE means major/full GC.
+	  It should be TRUE (minor marking).
+
 Thu Jun 20 02:44:45 2013  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* win32/win32.c (waitpid): should not return 0 but wait until exit
diff --git a/gc.c b/gc.c
index cd0188844a..f76b873971 100644
--- a/gc.c
+++ b/gc.c
@@ -3634,7 +3634,7 @@ gc_marks(rb_objspace_t *objspace, int minor_gc)
 		gc_free_stored_bitmaps(objspace, before_mark_stored_bitmaps);
 	    }
 	    else {
-		gc_marks_body(objspace, th, FALSE);
+		gc_marks_body(objspace, th, TRUE);
 	}
 	}