[R-pkg-devel] Build Environment for Mac OS Catalina

[Russell Almond]

I'm doing my development on an older version of Mac OS, running 
Catalina.  I'm a bit confused as to what the proper development 
environment is because the stuff on https://mac.r-project.org/tools 
seems to be for either more recent or older versions of MacOS.  I also 
seem to have screwed up something in my toolchain (the curious can see 
my question at 
https://stackoverflow.com/questions/71790401/otool-is-referencing-an-old-version-of-libffi 
).

I have a couple of related questions:

1) What is the right set of instructions for setting up the tool chain 
for Mac OS Catalina?

2) I'm currently using the R install from homebrew, but I thought I saw 
something about a different version of R that I should be using.  Is 
that still current advise?

Thanks, Googling the answers to these questions points me at some pages 
that are clearly out of date.