CarbonHeaders obsolete: uninstall dependencies

[René J.V. Bertin]

On Monday January 19 2015 13:30:24 Tim Johnson wrote:
> MacPorts base version 2.3.3 on OS X 10.7
> ----------------------------------------
> When executing
>   sudo port upgrade outdated
> I get the following message :
>   Error: CarbonHeaders is an obsolete port.  Please uninstall it
> When executing
>   sudo port uninstall CarbonHeaders

> Since I have only entry - level knowledge of macports, and I don't
> wish to do "damage" I'm must ask :
> 
> Is this just a matter of running 
>   sudo port libunwind-headers ?
> and then
>   sudo port uninstall CarbonHeaders ?

Yes, or `sudo port uninstall libunwind-headers CarbonHeaders`.

I somehow missed this obsolescence...
Why exactly have the CarbonHeaders gone obsolete, and what does removal mean for code that includes AvailabilityMacros.h? I've made a number of patches to KDE4 that rely on that header, and KDE uses Carbon itself.

R.