diff --git a/share/mk/sys.mk b/share/mk/sys.mk
index 897f720aab2..1bb9da6beee 100644
--- a/share/mk/sys.mk
+++ b/share/mk/sys.mk
@@ -35,8 +35,12 @@ CC		?=	c89
 CFLAGS		?=	-O
 .else
 CC		?=	cc
+.if ${MACHINE_ARCH} == "arm"
+CFLAGS		?=	-O -fno-strict-aliasing -pipe
+.else
 CFLAGS		?=	-O2 -fno-strict-aliasing -pipe
 .endif
+.endif
 
 CXX		?=	c++
 CXXFLAGS	?=	${CFLAGS:N-std=*:N-Wnested-externs:N-W*-prototypes}