diff --git a/ChangeLog b/ChangeLog
index 925fb581c5..9303fc1048 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+Wed Nov 20 17:34:13 2013  Koichi Sasada  <ko1@atdot.net>
+
+	* parse.y (rb_gc_mark_symbols): set global_symbols.minor_marked only
+	  when full_mark is 0.
+	  rb_gc_mark_symbols() (with full_mark == 1) can be called by other
+	  than GC (such as rb_objspace_reachable_objects_from_root()).
+
 Wed Nov 20 11:46:38 2013  NARUSE, Yui  <naruse@ruby-lang.org>
 
 	* ext/json: merge JSON 1.8.1.
diff --git a/parse.y b/parse.y
index ba5a8154a2..8207ad7133 100644
--- a/parse.y
+++ b/parse.y
@@ -10155,7 +10155,8 @@ rb_gc_mark_symbols(int full_mark)
 	rb_mark_tbl(global_symbols.id_str);
 	rb_gc_mark_locations(global_symbols.op_sym,
 			     global_symbols.op_sym + numberof(global_symbols.op_sym));
-	global_symbols.minor_marked = 1;
+
+	if (!full_mark) global_symbols.minor_marked = 1;
     }
 }
 #endif /* !RIPPER */