--- src_c/P2P/Makefile.orig	2021-10-01 13:09:19 UTC
+++ src_c/P2P/Makefile
@@ -50,7 +50,7 @@ BINARY:=IMB-P2P
 TARGET=P2P
 BINARY:=IMB-P2P
 
-override CFLAGS += -O3 -Wall -Wextra -pedantic -Wno-long-long
+override CFLAGS += -Wall -Wextra -pedantic -Wno-long-long
 override LDFLAGS += -lm
 
 ifeq ($(origin CC),default)
