title: What does a colon in makefile dependencies list means?
body: <p>I'm working on a project using makefile. Some of the make rules have the following format:</p>
  
  <pre><code>a.o b.o c.o : %.o : %.c
      gcc -c $&lt; -o $@
  </code></pre>
  
  <p>What's the meaning of such a rule? I'm unable to find explanation in the official manual, but I guess it's used for applying pattern-matching on only the *.o files listed as targets. Is that correct?</p>