-GENERIC_PATCH_DIR := $(GENERIC_PLATFORM_DIR)/patches$(shell [ -d "$(GENERIC_PLATFORM_DIR)/patches-$(KERNEL_PATCHVER)" ] && printf -- "-$(KERNEL_PATCHVER)" || true )
-GENERIC_FILES_DIR := $(GENERIC_PLATFORM_DIR)/files$(shell [ -d "$(GENERIC_PLATFORM_DIR)/files-$(KERNEL_PATCHVER)" ] && printf -- "-$(KERNEL_PATCHVER)" || true )
+GENERIC_PATCH_DIR := $(GENERIC_PLATFORM_DIR)/patches$(if $(wildcard $(GENERIC_PLATFORM_DIR)/patches-$(KERNEL_PATCHVER)),-$(KERNEL_PATCHVER))
+GENERIC_FILES_DIR := $(foreach dir,$(wildcard $(GENERIC_PLATFORM_DIR)/files $(GENERIC_PLATFORM_DIR)/files-$(KERNEL_PATCHVER)),"$(dir)")