title: What is msr primask?
body: <p>I migrated a IAR project into Eclipse with IAR plugin. Then I wanted to switch from IAR compiler to GCC. And when I tried to compile I got this error:</p>
  
  <blockquote>
    <p>Error: selected processor does not support requested special purpose register -- `msr primask,r3'</p>
  </blockquote>
  
  <p>What does this mean? What is <code>msr primask</code>? Can this be fixed under GCC?</p>