RStudio crashes when debugging


I updated my R to development version (to be able to use some packages developed with R 4.0.0 in mind). But since then I'm having a weird problem, I'm not sure how to make a reproducible example of. Any time I call debug on a function, and call that function for debugging, the RStudio sessions disconnects saying "R encountered a fatal error". In the grayed out console area the error message reads the following:

Error in (function (srcref) : unimplemented type (29) in 'eval'

This is true for debugging any functions (the ones I made or the ones offered by base R suh as mean function. When I try to use debugging in an R session (without RStudio) in terminal window, it seems to work suggesting there is something going on with the RStudio environment?

My machine runs Windows 10, and the r.version output is copied below:

platform       x86_64-w64-mingw32                                
arch           x86_64                                            
os             mingw32                                           
system         x86_64, mingw32                                   
status         Under development (unstable)                      
major          4                                                 
minor          0.0                                               
year           2019                                              
month          12                                                
day            05                                                
svn rev        77528                                             
language       R                                                 
version.string R Under development (unstable) (2019-12-05 r77528)
nickname       Unsuffered Consequences output is below:

R Under development (unstable) (2019-12-05 r77528)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 10 x64 (build 17763)

Matrix products: default

[1] LC_COLLATE=English_United States.1252  LC_CTYPE=English_United States.1252   
[3] LC_MONETARY=English_United States.1252 LC_NUMERIC=C                          
[5] LC_TIME=English_United States.1252    

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

loaded via a namespace (and not attached):
[1] compiler_4.0.0 tools_4.0.0   

Any help is appreciated!


Hi, I have the same issue on my Windows machine. The crash is very annoying and It can even occurs when loading a package, but this is not surprising since your are using "unstable" R. It seems like the problem is related to the incompatibility between R4.0 and Rstudio. The previous R version works fine with the same Rstudio.

1 Like

I am also getting this issue. It is specific to RStudio.
I can debug fine on the command line.
I am using R-devel.

We're tracking this issue on the RStudio side here:

1 Like

Update: we have fixed this issue. Please try the preview version, 1.2.5036-1 or newer, and let us know if it resolves the problem for you:


The update works for me when debugging.
Unfortunately, I am having issues with RStudio crashing, likely for other reasons.
This usually happens when I switch projects or start RStudio.
I've deleted my ~/.rstudio-desktop folder but it doesn't help.

I'm using:

Ubuntu Linux 19.10 (64-bit)
 - Graphics: NVE4
 - Kernel: Linux 4.15.0-33-generic
 - GNOME: 3.34.1
 - 16 Gb RAM
X.Org X Server Version: 1:7.7+19ubuntu12
R Version 4.0.0 r77629
RStudio Preview 1.2.5036-1

Image before freezing:

Confirming that I've had this issue with the current version of RStudio (1.2.5033) and with R-devel (2020-01-11 r77654), and that downloading the latest preview release of RStudio (1.2.5036) has resolved this issue for me.


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