title: Using --vanilla with R CMD build
body: <p>According to the document <em>Writing R Extensions</em> <a href="http://cran.r-project.org/doc/manuals/R-exts.html#Checking-and-building-packages" rel="nofollow">ss 1.3</a> "R CMD check and R CMD build run R with --vanilla, so none of the user's startup files are read". </p>
  
  <p>This doesn't seem to happen  on my installation. I have found that my version of R (2.15.1 on Mac) loads the packages in my <code>.Rprofile</code> - i am pretty sure about this, as i've managed to reliably break it by adding <code>library(hobblegobble)</code> to my <code>.Rprofile</code>. </p>
  
  <p>does this matter? If so, should i <em>always</em> prefer to build packages with </p>
  
  <pre><code>R --vanilla CMD build
  </code></pre>
  
  <p>thanks</p>