diff --git a/sys/boot/efi/libefi/Makefile b/sys/boot/efi/libefi/Makefile
index fc66e01..470453d 100644
--- a/sys/boot/efi/libefi/Makefile
+++ b/sys/boot/efi/libefi/Makefile
@@ -17,9 +17,6 @@ CFLAGS+= -I${.CURDIR}/../../../../lib/libstand
 # Pick up the bootstrap header for some interface items
 CFLAGS+= -I${.CURDIR}/../../common
 
- 
-# Suppress warning from clang for FreeBSD %b and %D formats
-CFLAGS+= -fformat-extensions
 CFLAGS+= -DTERM_EMU
 
 .include <bsd.lib.mk>
diff --git a/sys/boot/i386/libi386/Makefile b/sys/boot/i386/libi386/Makefile
index 24cc4c1..e5d2bae 100644
--- a/sys/boot/i386/libi386/Makefile
+++ b/sys/boot/i386/libi386/Makefile
@@ -55,9 +55,6 @@ CFLAGS+=	-I${.CURDIR}/../../common -I${.CURDIR}/../common \
 # the location of libstand
 CFLAGS+=	-I${.CURDIR}/../../../../lib/libstand/
 
-# Suppress warning from clang for FreeBSD %b and %D formats
-CFLAGS+= -fformat-extensions
-
 .if ${MACHINE_CPUARCH} == "amd64"
 CLEANFILES+=	machine
 machine: