 Yuchi Gong told him that he would not even try to kill Li Shimin before Qin Shubao was there, or he would die under the Zhijin Gate, a major gate in Chang'an.When Cheng Yaojin left, Li Shimin asked Yuchi Gong why he did not join Li's troop as he was from Taiyuan.Yuchi Gong was annoyed because he thought it was Li Shimin who affronted him in the camp.