lib/libc/Versions.def: new symbol version for 12.x

[Daniel Eischen]

On Fri, 29 Jul 2016, Ed Schouten wrote:

> Hi there,
>
> In a couple of weeks from now I'm going to add new versions of
> basename() and dirname() to libc that are thread-safe. These should
> now use symbol version "FBSD_1.5", but a question that emaste@ and I
> have is: why don't these symbol version names follow the major
> versions of FreeBSD? As in, why not call this "FBSD_12.0" instead?

New symbol versions can be rolled back to -stable or other prior
baselines.  Also, if there are no changes in a major release branch,
there's no need to bump the symbol version.  It's just an arbitrary
number somewhat tied to major release versions by convention.  I
started it at 1.0 when I first added symbol versioning, so you can
probably blame me ;-)

-- 
DE