# globally built with -Wcast-function-type.
KBUILD_CFLAGS += $(call cc-option, -Wcast-function-type)
+# To gain proper coverage for CONFIG_UBSAN_BOUNDS and CONFIG_FORTIFY_SOURCE,
+# the kernel uses only C99 flexible arrays for dynamically sized trailing
+# arrays. Enforce this for everything that may examine structure sizes and
+# perform bounds checking.
+KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
+
# disable stringop warnings in gcc 8+
KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)