Building custom minimal Linux from source.with cross compiling toolchain, etc.error fixdep.o.cmd:1:missing separator. Stop--Makefile error

Question

I cross compiled toolchain now building Linux kernel. I followed this page

https://www.linuxjournal.com/content/diy-build-custom-minimal-linux-distribution-source

So I compiled all the tools including gcc, etc. When I reached compiling linux-4.16.3 kernel, with this command

  make ARCH=${LJOS_ARCH} CROSS_COMPILE=${LJOS_TARGET}- INSTALL_MOD_PATH=${LJOS}

I got following error

root@this:/home/ubuntu/source/linux-4.16.3# CHK     include/config/kernel.release
  CHK     include/generated/uapi/linux/version.h
  CHK     include/generated/utsrelease.h
  CHK     include/generated/bounds.h
  CHK     include/generated/timeconst.h
  CHK     include/generated/asm-offsets.h
  CALL    scripts/checksyscalls.sh
  DESCEND  objtool
Makefile:49: warning: overriding recipe for target '/home/ubuntu/source/linux-4.16.3/tools/objtool/'
Makefile:46: warning: ignoring old recipe for target '/home/ubuntu/source/linux-4.16.3/tools/objtool/'
/home/ubuntu/source/linux-4.16.3/tools/objtool/.fixdep.o.cmd:1: *** missing separator.  Stop.
make[3]: *** [Makefile:43: /home/ubuntu/source/linux-4.16.3/tools/objtool/fixdep-in.o] Error 2
make[2]: *** [/home/ubuntu/source/linux-4.16.3/tools/build/Makefile.include:4: fixdep] Error 2
make[1]: *** [Makefile:63: objtool] Error 2
make: *** [Makefile:1687: tools/objtool] Error 2

Now apparently it looks like the Makefile in /home/ubuntu/source/linux-4.16.3/tools/objtool/ has something wrong at line line 43,and line 63

Or while running the scripts/checksyscalls.sh it got stuck with something that was causing a problem. Like something that the script is doing but that command not found I am completely clueless what might causing problem. In the link above the author downloaded Busybox, so I believe it had something that needed to be installed but I didn't.

What does the error mean, and why is it happening?