diff --git a/src/Makefile b/src/Makefile
index d5b2e9626..0826298bb 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -3,7 +3,7 @@ APPCLIENT = $(APPNAME)
 APPSERVER = $(APPNAME)_server
 
 #CXXFLAGS = -ggdb3
-CXXFLAGS ?= -O3 -fomit-frame-pointer -ffast-math -fno-finite-math-only
+CXXFLAGS = -O3 -fomit-frame-pointer -ffast-math -fno-finite-math-only
 override CXXFLAGS += -Wall -fsigned-char -fno-exceptions -fno-rtti -Wno-invalid-offsetof -std=c++17
 PLATFORM = $(shell $(CC) -dumpmachine)
 RMFLAGS = -fv
diff --git a/src/enet/Makefile b/src/enet/Makefile
index aaca02aec..87913d7a2 100644
--- a/src/enet/Makefile
+++ b/src/enet/Makefile
@@ -1,4 +1,4 @@
-CFLAGS?=-O3 -fomit-frame-pointer
+CFLAGS=-O3 -fomit-frame-pointer
 override CFLAGS:= $(CFLAGS) -Iinclude $(shell ./check_cflags.sh $(CC) $(CFLAGS))
 
 OBJS= \