RKWard and R 4.0.0 - Important bug and workaround

[Pierre de Villemereuil]

Hi Thomas and others,

FYI, it seems a release date (6th June) for R 4.0.1 was decided today:
https://stat.ethz.ch/pipermail/r-devel/2020-May/079577.html

Cheers,
Pierre

Le dimanche 24 mai 2020, 10:14:17 CEST Thomas Friedrichsmeier a écrit :
> Hi!
> 
> This is a note of caution about using RKWard with R 4.0.0:
> 
> -- Problem --
> 
> There is a bug in R 4.0.0 with respect to active bindings, which RKWard
> is relatively likely to trigger. Running the following code *twice*
> will render your RKWard session unusable, and **could result in
> loss of data**:
> 
>   for (i in 1:2) { print (i) }
> 
> Note that this affects top-level statements, only, i.e. in general code
> that you enter in the console of run from a script, directly. Not code
> in packages or RKWard plugins.
> 
> -- Workaround --
> 
> If you have the choice, please delay upgrading R until R 4.0.1 is
> released.
> 
> If you have already installed R 4.0.0, you should set the option
> 
>   compiler::enableJIT(2)  # or a lower value
> 
> in each session. This can also be made permanent by copying it into
> the field "Futher option commands to run in each session" in
> Settings->Configure RKWard->R-Backend.
> 
> -- Outlook --
> 
> The bug has been fixed in R devel, but no release date has been set to
> R 4.0.1, yet. I will probably create a "bugfix"-release that enables
> the above workaround by default in the coming day. Meanwhile I have
> started working on a new approach to object modification detection that
> does not rely on active bindings.
> 
> Regards
> Thomas
>