title: RStudio crashes when trying to fit lm Ubuntu 18.04
body: <p>I'm attempting to run some code, example from a textbook called "Design and Analysis of Experiments with R". It runs fine using R console or from ESS and Emacs, but in RStudio crashes.  Have I got something set incorrectly?  I've tried other sections of code and anything that seems to fit a model causes it to crash.</p>
  
  <p>Ubuntu 18.04, RStudio 1.1.456, R 3.5.1.  Here is the offending code</p>
  
  <pre><code>Example 3 p. 24
  rm(bread)
  library(daewr)
  mod0 &lt;-lm( height ~ time, data = bread )
  summary (mod0)
  </code></pre>
  
  <p>Crash screen
  <a href="https://i.stack.imgur.com/JuoMi.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/JuoMi.png" alt="enter image description here"></a></p>