Remove add-ons mechanism

[Zack Weinberg]

On Thu, Sep 28, 2017 at 1:49 PM, Joseph Myers <joseph@codesourcery.com> wrote:
>
> Add-ons involve significant, little-used complexity in the glibc build
> system, and make it hard to understand what the space of possible
> glibc configurations is.  This patch removes the add-ons mechanism.

I don't disagree with this patch exactly, but I was thinking of using
the add-ons mechanism to prototype a CSPRNG addition to glibc and I'd
like to ask how you think that should be done instead (and more
generally, how you think new features that people might want to
experiment with but that are not yet ready for prime time should be
distributed -- branches are Not Great, as one has to keep rebasing
them)

zw