I have upgraded R (from 3.6 to 4.0) and RStudio (from 1.1 to 1.2.5) a few days ago, and Ubuntu from 18.04 to 20.04 yesterday.
Since then, R sometimes never terminates when executing certain commands: ivreg (from package AER), summary (of a logit regression) and logitmfx (from package mfx). Sometimes these commands run fine, but most of the time I have to kill the process (killall rstudio) because R won't terminate the execution, even when pressing the red Stop button in RStudio.
When I tried example('AER'), it worked fine. Then I re-installed the package AER. It threw 10 warnings of type In readLines(file, skipNul = TRUE) : cannot open compressed file '/usr/lib/R/site-library/[package]/DESCRIPTION', probable reason 'No such file or directory' where [package] is abind, colorspace, dichromat... (but not AER).
Since then example('AER') throws a warning: no help found for ‘AER’.
I've removed and reinstalled R 4.0: it didn't help. Besides, the apt purge r-base* r-recommended r-cran-* threw a warning: dpkg: warning: while removing r-base-core, directory '/usr/lib/R/site-library' not empty so not removed. Also, there was a bunch of Package [package] is not installed, so not removed, including for [package] equal to r-cran-abind and the other listed above (this purge also returned a bunch of Note, selecting [package] for glob 'r-cran-*').
I haven't tried using R without RStudio. I was probably working on RStudio during the upgrade to Ubuntu 20.04. Also, I can't recall if this issue started after I upgraded R and RStudio (which would be my best guess) or after I upgraded Ubuntu (a day or two later).
I hope someone can help.
