Index: head/sys/boot/i386/boot2/Makefile
===================================================================
--- head/sys/boot/i386/boot2/Makefile
+++ head/sys/boot/i386/boot2/Makefile
@@ -38,6 +38,7 @@
 	-Winline
 
 CFLAGS.gcc+=	-Os \
+		-fno-asynchronous-unwind-tables \
 		--param max-inline-insns-single=100
 .if ${COMPILER_TYPE} == "gcc" && ${COMPILER_VERSION} <= 40201
 CFLAGS.gcc+=   -mno-align-long-strings