# www.lufa-lib.org
#
-LUFA_BUILD_MODULES += DFU
-LUFA_BUILD_TARGETS += flip flip-ee dfu dfu-ee
-LUFA_BUILD_MANDATORY_VARS += MCU TARGET
-LUFA_BUILD_OPTIONAL_VARS +=
+LUFA_BUILD_MODULES += DFU
+LUFA_BUILD_TARGETS += flip flip-ee dfu dfu-ee
+LUFA_BUILD_MANDATORY_VARS += MCU TARGET
+LUFA_BUILD_OPTIONAL_VARS +=
+LUFA_BUILD_PROVIDED_VARS +=
+LUFA_BUILD_PROVIDED_MACROS +=
# -----------------------------------------------------------------------------
# LUFA DFU Bootloader Buildsystem Makefile Module.
#
# (None)
#
+# PROVIDED VARIABLES:
+#
+# (None)
+#
+# PROVIDED MACROS:
+#
+# (None)
+#
# -----------------------------------------------------------------------------
-ERROR_IF_UNSET = $(if $(filter undefined, $(origin $(strip $(1)))), $(error Makefile $(strip $(1)) value not set))
-ERROR_IF_EMPTY = $(if $(strip $($(strip $(1)))), , $(error Makefile $(strip $(1)) option cannot be blank))
-ERROR_IF_NONBOOL = $(if $(filter Y N, $($(strip $(1)))), , $(error Makefile $(strip $(1)) option must be Y or N))
+SHELL = /bin/sh
+
+ERROR_IF_UNSET ?= $(if $(filter undefined, $(origin $(strip $(1)))), $(error Makefile $(strip $(1)) value not set))
+ERROR_IF_EMPTY ?= $(if $(strip $($(strip $(1)))), , $(error Makefile $(strip $(1)) option cannot be blank))
+ERROR_IF_NONBOOL ?= $(if $(filter Y N, $($(strip $(1)))), , $(error Makefile $(strip $(1)) option must be Y or N))
# Sanity-check values of mandatory user-supplied variables
$(foreach MANDATORY_VAR, $(LUFA_BUILD_MANDATORY_VARS), $(call ERROR_IF_UNSET, $(MANDATORY_VAR)))
-$(call ERROR_IF_UNSET, MCU)
-$(call ERROR_IF_UNSET, TARGET)
$(call ERROR_IF_EMPTY, MCU)
$(call ERROR_IF_EMPTY, TARGET)