Hello All, I was going through the linux kernel newbie articles in kernelnewbies.com and found it very interesting. I downloaded the tarballs for the 0.01 version of kernel from : http://www.kernel.org/pub/linux/kernel/Historic/ Then the next thing I was trying to do was to compile the source code and try to understand the various methods/function calls, system calls etc, but I'm not able to compile the code, I'm getting the following errors: $ make -f Makefile gas -c -o boot/head.o boot/head.s make: gas: Command not found make: *** [boot/head.o] Error 127 Then I searched in the web for GAS and found that it GNU AS. I've "as" installed in my box, so I tried creating a symlink with the name "gas" but then bumped into another error: $ make gas -c -o boot/head.o boot/head.s gas: unrecognized option `-c' make: *** [boot/head.o] Error 1 Is GNU AS same as "as" ? when running version check I got this: $ as --version GNU assembler (GNU Binutils) 2.20.51.20100410 Copyright 2010 Free Software Foundation, Inc. This program is free software; you may redistribute it under the terms of the GNU General Public License version 3 or later. This program has absolutely no warranty. This assembler was configured for a target of `i686-cygwin'. I tried searching on the web to find ways to install "GNU AS" but could not get any useful info. I'm facing similar problem with "GNU LD". Is it different from the "ld": $ ld --version GNU ld (GNU Binutils) 2.20.51.20100410 Copyright 2010 Free Software Foundation, Inc. This program is free software; you may redistribute it under the terms of the GNU General Public License version 3 or (at your option) a later version. This program has absolutely no warranty. Can someone help me installing these two or let me know what is the fix for the same. I'm running cygwin on Win7-64 bit Thanks