`
  if (nCheckDepth <= 0)
      nCheckDepth = 1000000000; // suffices until the year 19000
  if (nCheckDepth > chainActive.Height())
      nCheckDepth = chainActive.Height();
  ````

  These lines confuse me.
  Correct me if I am wrong, but we can't check any more blocks than we have right?
  If someone requests <= 0 it get set it into some huge number and then immediately limit it to the chain height in the following statement.
  ````
  if (nCheckDepth > chainActive.Height())
      nCheckDepth = chainActive.Height();
  ````
  when using ````--checkblocks=Z```` When Z is ````0```` or any other negative number, it will check all blocks.

  I think it should be changed to this maybe.
  ````
  if (nCheckDepth <= 0 || nCheckDepth > chainActive.Height())
      nCheckDepth = chainActive.Height();
  ````
  Which gets rid of that huge number which is confusing for any other altcoins that have a different block time.