D-Programming-GDC/GDC — pull request #47 by jpf91 (2013-02-07 19:13:20+00:00)
Title: Use gcc's config system for predefined OS versions

This implements the OS versions the gcc way.
```target-ver-syms.sh``` is still kept to define the ```TARGET_*``` macros for the frontend. It should be removed later (probably when your target changes in pull 1626 have made it back to gdc).