GCC build on Windows

GCC relies on POSIX (Portable Operating System Interface) functionality which is not available in Windows natively. Hence for building GCC on windows, a linux-like environment for Windows is used. The linux-like environment for windows is brought via:

1. cygwin (or)
   
2. MinGW (Minimalist GNU for Windows)
   

Both cygwin and MinGW output windows executable ('.exe' file). But the executable built on cygwin has the cygwin DLL dependency (I.e. The GCC compiler executable to run, the required cygwin DLLs should be made available to the executable). Whereas the executable built on MinGW has no such dependency.