make出错

yufeng1009

编译hello 时，提示：Makefile:1: ***missing  separator.  stop.　是什么问题？也都用tab键了啊
Makefile如下：
ifeq($(KERNELRELEASE),)
        KERNELDIR ?= /lib/modules/$(shell uname -r)/build
        PWD := $(shell pwd)
modules:
        $(MAKE) -C $(KERNELDIR) M=$(PWD) modules
modules_install:
        $(MAKE) -C $(KERNELDIR) M=$(PWD) modules_install
clean:
        rm -rf *.o *~ core .depend .*.cmd *.ko *.mod.c .tmp_versions .PHONY: modules modules_install clean
else
        obj-m :=hello.o
endif

ingdxdy

ifeq ($(KERNELRELEASE),)
        KERNELDIR ?= /lib/modules/$(shell uname -r)/build
        PWD := $(shell pwd)

看到不同了吗？
ifeq后面加一个空格！