Make error: missing separator

Question

I am getting the following error running make:

Makefile:168: *** missing separator.  Stop.

What is causing this?

Answer 1

Following Makefile code worked:

obj-m = hello.o

all:
    $(MAKE) -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules 

clean:
    $(MAKE) -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean