Deprecate union wait and remove support from wait functions [BZ #19613]

[Florian Weimer]

On 02/12/2016 05:26 PM, Florian Weimer wrote:
> The overloading approach in the macros was incompatible with integer
> expressions of a type different from int.  Applications using union wait
> and these macros will have to migrate to the POSIX-specified int
> status type.
> 
> This commit also removes the transparent union overloads from the
> process wait functions.  As a result, application code which uses
> union wait will receive compile-time warnings about pointer
> compatibility.
> 
> This does not have ABI impact.  The functionality was deprecated in BSD
> in the early 1990s.  I plan to remove union wait completely in glibc 2.25.

Ping?

I'd like to have some buy-in for this API change.

Thanks,
Florian