title: Calling makefile in a subdirectory
body: <p>I have a source code folder structure as follows</p>
  
  <pre><code>src
   |-tests
   |-abc
  </code></pre>
  
  <p>I have a makefile in <code>src</code> which has a target called <code>tests</code>. <code>tests</code> has its own <code>makefile</code> which it uses to compile the source code into binary.(multiple targets).All that is managed by the Makefile in the test directory.</p>
  
  <p>My <code>src</code> make file has the following targets.</p>
  
  <pre><code>all: main tests
  
  main: $(DEPENDENCY IN SRC and ABC)
     command
  
  tests: ??
       make -C tests
  </code></pre>
  
  <p>What dependancy can I specify for tests target in the main Makefile.. I don't want this Makefile to be aware of the source files in the tests folder.</p>