-obj-$(CONFIG_ACPI_BOOT) := boot.o
-boot-$(CONFIG_ACPI_BOOT) := ../../../i386/kernel/acpi/boot.o
+obj-y := boot.o
+boot-y := ../../../i386/kernel/acpi/boot.o
obj-$(CONFIG_ACPI_SLEEP) += sleep.o wakeup.o
+
+ifneq ($(CONFIG_ACPI_PROCESSOR),)
+obj-y += processor.o
+endif
+