title: Makefiles, targets as dependencies
body: <p>I'm new to Makefiles and I'm trying to debug something that extends over multiple Makefiles.</p>
  <blockquote>
  <p>target2: target1</p>
  <p>command 1</p>
  </blockquote>
  <p>Target 1 builds the source code (takes about ~4 hours). Target 2 is simply supposed to copy resulting files into certain directories.</p>
  <p>I've already made target 1. When I immediately try to make target 2, it seems to think it is missing some files/libraries and rebuilds for ~5-10 mins. The files have not been moved or changed. I can executed target 2 immediately after target 1 and it will ALWAYS rebuild for a few minutes.</p>
  <p>Target 1 and command 1 are creating the same directory. Is it possible that the timestamp on this directory is causing the rebuilding of these libraries? Or is it only files that will trigger rebuilding with timestamp discrepancy?</p>