build(makefile): add helper to detect linker options
This is a small helper to check for possible linker options. If the
linker supports the requested option it is returned and if not nothing
will be returned, e.g.:
TF_LDFLAGS += $(call ld_option, --no-warn-rwx-segments)
can be called unconditional.
Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Change-Id: I236800852ece49948ff53a0b91fddba53c8f0f95
diff --git a/make_helpers/build_macros.mk b/make_helpers/build_macros.mk
index 4815efa..89f43f2 100644
--- a/make_helpers/build_macros.mk
+++ b/make_helpers/build_macros.mk
@@ -87,6 +87,12 @@
$(foreach num,$1,$(eval $(call assert_numeric,$(num))))
endef
+# Convenience function to check for a given linker option. An call to
+# $(call ld_option, --no-XYZ) will return --no-XYZ if supported by the linker
+define ld_option
+ $(shell if $(LD) $(1) -v >/dev/null 2>&1; then echo $(1); fi )
+endef
+
# CREATE_SEQ is a recursive function to create sequence of numbers from 1 to
# $(2) and assign the sequence to $(1)
define CREATE_SEQ