title: Parser error, symbols undefined in mips program
body: <p>I keep getting this error:</p>
  
  <pre><code>spim: (parser) parse error on line 26 of file jc4137.s
    li    $t0, $a0 # t0 = str
             ^
  The following symbols are undefined:
  main
  t
  </code></pre>
  
  <p>I was wondering what this is? </p>
  
  <p>The chunk of code is this:</p>
  
  <pre><code>ispalindrome:
      li      $v0, 0
      li      $s0, 0 # length of str
      li      $t0, $a0 # t0 = str
  </code></pre>