title: Debugging SCons
body: <p>I've written a rather complicated set of SCons scripts, and I have some errors I cannot find, for example intermediate files are removed or there are cyclic dependencies reported, and I want to know the reason. Unfortunately, I don't see any means to get good verbose debugging output of what SCons is doing and where. For example, the option <code>--taskmastertrace=FILE</code> does not explain why my intermediate files were deleted. (EDIT: of course I can protect them using <code>Precious</code>, but those files are <em>needed</em> for another target and the build fails -- I just don't see why they are deleted. My current solution involves <code>Precious</code>, but it's not a real fix for the issue).</p>
  
  <p>I'd like to get a trace of everything going on, including dependency changes, file creations and deletions, and other operations. Is there any way to enable such verbose logging? I'm a little stuck with my project currently.</p>
  
  <p>Cheers,
  H.</p>