[#262] Fixed memory leak in expression_util during trace logging
[#262] Fixed memory leak in expression_util during trace logging

seojungmin/peloton,AllisonWang/peloton,cmu-db/peloton,wangziqi2016/peloton,apavlo/peloton,yingjunwu/peloton,haojin2/peloton,vittvolt/15721-peloton,AllisonWang/peloton,seojungmin/peloton,AngLi-Leon/peloton,vittvolt/15721-peloton,yingjunwu/peloton,malin1993ml/peloton,apavlo/peloton,PauloAmora/peloton,wangziqi2016/peloton,AngLi-Leon/peloton,ShuxinLin/peloton,phisiart/peloton-p3,ShuxinLin/peloton,PauloAmora/peloton,phisiart/peloton-p3,haojin2/peloton,PauloAmora/peloton,vittvolt/15721-peloton,jessesleeping/iso_peloton,ShuxinLin/peloton,PauloAmora/peloton,haojin2/peloton,prashasthip/peloton,vittvolt/peloton,malin1993ml/peloton,eric-haibin-lin/peloton-1,wangziqi2016/peloton,malin1993ml/peloton,vittvolt/peloton,cmu-db/peloton,ShuxinLin/peloton,phisiart/peloton-p3,yingjunwu/peloton,prashasthip/peloton,cmu-db/peloton,vittvolt/peloton,yingjunwu/peloton,jessesleeping/iso_peloton,cmu-db/peloton,AllisonWang/peloton,haojin2/peloton,prashasthip/peloton,apavlo/peloton,cmu-db/peloton,yingjunwu/peloton,jessesleeping/iso_peloton,prashasthip/peloton,yingjunwu/peloton,apavlo/peloton,ShuxinLin/peloton,vittvolt/15721-peloton,seojungmin/peloton,haojin2/peloton,haojin2/peloton,eric-haibin-lin/peloton-1,AllisonWang/peloton,ShuxinLin/peloton,prashasthip/peloton,jessesleeping/iso_peloton,malin1993ml/peloton,seojungmin/peloton,PauloAmora/peloton,AngLi-Leon/peloton,AllisonWang/peloton,vittvolt/peloton,phisiart/peloton-p3,AllisonWang/peloton,seojungmin/peloton,seojungmin/peloton,AngLi-Leon/peloton,cmu-db/peloton,jessesleeping/iso_peloton,apavlo/peloton,PauloAmora/peloton,jessesleeping/iso_peloton,phisiart/peloton-p3,prashasthip/peloton,vittvolt/peloton,malin1993ml/peloton,wangziqi2016/peloton,AngLi-Leon/peloton,vittvolt/peloton,eric-haibin-lin/peloton-1,malin1993ml/peloton,wangziqi2016/peloton,eric-haibin-lin/peloton-1,phisiart/peloton-p3,eric-haibin-lin/peloton-1,apavlo/peloton,wangziqi2016/peloton,eric-haibin-lin/peloton-1,vittvolt/15721-peloton,AngLi-Leon/peloton,jessesleeping/iso_peloton,vittvolt/15721-peloton