Fixed building error

src/realtime.mk

@@ -1,24 +1,48 @@
 include ../config.mk
 include Kbuild
 
-include $(MODINC)
+cc-option = $(shell if $(CC) $(CFLAGS) $(1) -S -o /dev/null -xc /dev/null \
+             > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi ;)
+
+.PHONY: all clean install
 
 ifeq ($(BUILDSYS),kbuild)
 
-# dirty workaround to get the RTAI directory
+module = $(patsubst %.o,%.ko,$(obj-m))
-RTAIINCDIR = $(subst /rtai.h,,$(firstword $(wildcard $(foreach i,$(subst -I,,$(filter -I%,$(RTFLAGS))), $(i)/rtai.h))))
+
-ifneq ($(RTAIINCDIR),)
+ifeq (,$(findstring -Wframe-larger-than=,$(EXTRA_CFLAGS)))
-  RTAIDIR = $(realpath $(RTAIINCDIR)/..)
+  EXTRA_CFLAGS += $(call cc-option,-Wframe-larger-than=2560)
 endif
 
-all:
+$(module):
 	$(MAKE) EXTRA_CFLAGS="$(EXTRA_CFLAGS)" KBUILD_EXTRA_SYMBOLS="$(RTLIBDIR)/Module.symvers $(RTAIDIR)/modules/ethercat/Module.symvers" -C $(KERNELDIR) SUBDIRS=`pwd` CC=$(CC) V=0 modules
 
+clean::
+	rm -f $(obj-m)
+	rm -f *.mod.c .*.cmd
+	rm -f modules.order Module.symvers
+	rm -rf .tmp_versions
+
 else
 
-LDFLAGS += -Wl,-rpath,$(LIBDIR) -L$(LIBDIR) -llinuxcnchal -lethercat
+module = $(patsubst %.o,%.so,$(obj-m))
 
-all: modules
+EXTRA_CFLAGS := $(filter-out -Wframe-larger-than=%,$(EXTRA_CFLAGS))
+
+$(module): $(lcec-objs)
+	$(CC) -shared -o $@ $(lcec-objs) -Wl,-rpath,$(LIBDIR) -L$(LIBDIR) -llinuxcnchal -lethercat -lrt
+
+%.o: %.c
+	$(CC) -o $@ $(EXTRA_CFLAGS) -Os -c $<
 
 endif
 
+all: $(module)
+
+clean::
+	rm -f $(module)
+	rm -f $(lcec-objs)
+
+install: $(module)
+	mkdir -p $(DESTDIR)$(RTLIBDIR)
+	cp $(module) $(DESTDIR)$(RTLIBDIR)/