[Rd] switch to reference counting in R-devel

[Tierney, Luke]

R-devel has been switched to use reference counting by default with
r77508. Building with -DSWITCH_TO_NAMED goes back to the NAMED
mechanism.

Best,

luke

On Sun, 24 Nov 2019, luke-tierney using uiowa.edu wrote:

> Baring any unforeseen issues R-devel will switch in about a week from
> the NAMED mechanism to reference counting for determining when objects
> can be safely mutated in base C code. This is expected to have minimal
> impact on packages not using unsupported coding practices in their C
> code.
>
>
> The transition to reference counting has been in progress for a
> number of years. Some older notes on this are available at
> http://developer.r-project.org/Refcnt.html.  These may no longer be
> completely accurate but should give you an idea of what is going on.
>
> If you want to test your package under reference counting you can do
> so by building R with -DSWITCH_TO_REFCNT added to CFLAGS or DEFS in a
> config.site file.
>
> A small number of packages are still using the NAMED or SET_NAMED
> functions even though this has been discouraged for some  time.
> For now these will not produce errors but also not do anything useful.
> They will probably be removed before R 4.0.0 is released, so you
> should look at why you are using them and adjust accordingly.
>
> Best,
>
> luke
>
>
>

-- 
Luke Tierney
Ralph E. Wareham Professor of Mathematical Sciences
University of Iowa                  Phone:             319-335-3386
Department of Statistics and        Fax:               319-335-3017
    Actuarial Science
241 Schaeffer Hall                  email:   luke-tierney using uiowa.edu
Iowa City, IA 52242                 WWW:  http://www.stat.uiowa.edu