Downloading Files
1) Download and install Virtual Machine. Any modern virtual machine capable of making snapshots will do, for example VMware. This tutorial assumes Oracle VirtualBox because it's available free of charge.
2) Download Ubuntu Desktop Installation DVD: 16.04 LTS for amd64 will do. We need it to build Linux API headers in native environment. Any other Linux with development tools will do, but we assume Ubuntu 16.04 LTS for amd64 in this tutorial.
3) Download source code for gcc, binutils and glibc from ftp://ftp.gnu.org/ . You should have determined versions of the software previously.
4) Download additional patch for glibc from this website. It is required to build glibc under Cygwin.
5) Download source code for libraries gcc depends on: gmp, mpfr and mpc. We will use gmp-5.1.2, mpfr-3.1.2 and mpc-1.0.2 in this tutorial, but generally latest versions of all of them is what you need.
6) Download source code for Linux kernel. It is required to supply Linux API headers to build glibc from. Ideally, you need to download kernel version reported by "uname -r" in the target system.
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