diff --git a/ChangeLog b/ChangeLog
index 0c9b7ae322..0323379a93 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Mon Jun  8 05:09:58 2015  Koichi Sasada  <ko1@atdot.net>
+
+	* gc.c (obj_info): print method id for T_IMEMO/ment.
+
 Sun Jun  7 07:05:43 2015  Kazuki Tanaka  <gogotanaka@ruby-lang.org>
 
 	* Move test cases from test/ruby/test_complex.rb to test/test_cmath.rb
diff --git a/gc.c b/gc.c
index 3a6bc5c99d..ebd36cc3e8 100644
--- a/gc.c
+++ b/gc.c
@@ -8924,7 +8924,8 @@ obj_info(VALUE obj)
 	}
 	snprintf(buff, OBJ_INFO_BUFFERS_SIZE, "%s %s", buff, imemo_name);
 	if (imemo_type(obj) == imemo_ment) {
-	    snprintf(buff, OBJ_INFO_BUFFERS_SIZE, "%s (type: %d)", buff, RANY(obj)->as.imemo.ment.def->type);
+	    const rb_method_entry_t *me = &RANY(obj)->as.imemo.ment;
+	    snprintf(buff, OBJ_INFO_BUFFERS_SIZE, "%s (called_id: %s, type: %d)", buff, rb_id2name(me->called_id), me->def->type);
 	}
       }
       default: