It isn't as simple as --version.  The string output from --version is free form and can contain things in no particular format.

```ubuntu@ubuntu:~$ i686-w64-mingw32-g++ --version 
i686-w64-mingw32-g++ (GCC) 4.6.3
Copyright (C) 2011 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.```

```[warren@localhost gitian-builder]$ gcc --version
gcc (GCC) 4.8.1 20130603 (Red Hat 4.8.1-1)
Copyright (C) 2013 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.```

Even this separate approach fails to get a plain version number.

```[warren@localhost gitian-builder]$ gcc -E -dM $(mktemp --suffix=.h) |grep __VERSION__
#define __VERSION__ "4.8.1 20130603 (Red Hat 4.8.1-1)"```

Please suggest a specific command line approach that is guaranteed to get the plain x.y.z version number.  Otherwise I am not going to change this.