diff --git a/Makefile.mk b/Makefile.mk
index 73f2759fb..d55d1a49e 100644
--- a/Makefile.mk
+++ b/Makefile.mk
@@ -190,7 +190,7 @@ CFLAGS_WERROR ?= -Werror
 CFLAGS_WFATAL_ERRORS ?= -Wfatal-errors
 
 # Optimizations
-CFLAGS_OPTIMIZE ?= -O3 -flto
+CFLAGS_OPTIMIZE ?= -Os -flto
 CFLAGS_NO_OPTIMIZE ?= -O0
 LDFLAGS_OPTIMIZE ?=
 LDFLAGS_NO_OPTIMIZE ?=