diff --git a/openair1/SIMULATION/LTE_PHY/Makefile b/openair1/SIMULATION/LTE_PHY/Makefile
index 6f6bc10226b3e8e40f6323250cd05caf96fa2c88..be43ff4c84e0067bd55c6abb5b0b5f593e181e83 100644
--- a/openair1/SIMULATION/LTE_PHY/Makefile
+++ b/openair1/SIMULATION/LTE_PHY/Makefile
@@ -10,7 +10,7 @@ OPENAIR1_TOP = $(OPENAIR1_DIR)
 OPENAIR2_TOP = $(OPENAIR2_DIR)
 OPENAIR3 = $(OPENAIR3_DIR)
 
-CFLAGS = -g -ggdb -Wno-strict-aliasing -rdynamic -DMAX_NUM_CCs=1 -Wall -DPHYSIM -DNODE_RG -DUSER_MODE -DNB_ANTENNAS_RX=2 -DNB_ANTENNAS_TXRX=2 -DNB_ANTENNAS_TX=2 -DPHY_CONTEXT=1 $(CPUFLAGS) -DMALLOC_CHECK_=1 -DENABLE_VCD_FIFO # -Wno-packed-bitfield-compat
+CFLAGS = -O2 -g -ggdb -Wno-strict-aliasing -rdynamic -DMAX_NUM_CCs=1 -Wall -DPHYSIM -DNODE_RG -DUSER_MODE -DNB_ANTENNAS_RX=2 -DNB_ANTENNAS_TXRX=2 -DNB_ANTENNAS_TX=2 -DPHY_CONTEXT=1 $(CPUFLAGS) -DMALLOC_CHECK_=1 -DENABLE_VCD_FIFO # -Wno-packed-bitfield-compat
 
 
 # DCI Debug