title: Post-build step for multiple targets
body: <p>I have a makefile that has multiple targets for outputting data in different formats, e.g. <code>make html</code>, <code>make pdf</code>, <code>make txt</code> etc. and I would like to have pre-build and post-build steps that run when any of these options are used. I have the pre-build step sorted, but not sure how I can get the post-build step working properly.</p>
  
  <pre><code>.PHONY: html pdf txt pre-build post-build
  
  pre-build:
      do-pre-build-stuff
  
  post-build:
      do-post-build-stuff
  
  html: data.dat
      generate-html data.dat
  
  pdf: data.dat
      generate-pdf data.dat
  
  txt: data.dat
      generate-txt data.dat
  
  data.dat: pre-build
      generate-some-data &gt; data.dat
  </code></pre>
  
  <p>How can I get the <code>post-build</code> step to run after every target?</p>