So... now I have another problem 
I can't reinstall ddalpha and get this error message:
Error in system2(file.path(R.home("bin"), "R"), c(if (nzchar(arch)) paste0("--arch=", :
cannot popen ' '/usr/lib64/R/bin/R' --no-save --slave 2>&1 < '/tmp/RtmpU4dXOt/file3fb5b89c507'', probable reason 'Cannot allocate memory'
Considering that I have 16Gb of RAM and usually never get even close to using it all, I am a little surprised... This is likely to be an Arch Linux problem and not an R problem though. So I will post on the Arch Linux forum if nobody can help here.
Thanks! Updating R usually goes so smoothly...