title: Gcov works, but Gcovr doesn't work
body: <p>When I run  gcov  then the output says 87% covered... then I want to use gcovr, but it does never work. I tried to run from many directories, with lots of options. In some cases, a few files I get coverage but not the file I want to see.</p>
  
  <p>My project consists of 3 files:</p>
  
  <ul>
  <li><code>src\main.c</code></li>
  <li><code>src\makefile</code></li>
  <li><code>tst\test1.c</code></li>
  <li><code>tst\test2.c</code></li>
  <li><code>tst\makefile</code></li>
  <li><code>tst\obj\all</code> object files, gcno, gcda are stored here...</li>
  <li><code>build\build.bat</code> to make the project (windows)</li>
  </ul>
  
  <p>Should I change the directory structure? How to see which version of gcov I should use? 
  I want to see the coverage for main.c, but only get the coverage for test1.c and test2.c and those are not relevant for coverage!!</p>
  
  <p>Next to the test files, I have include directories on C:\compiler which are not required for coverage.</p>
  
  <p>I tried Python27:</p>
  
  <pre><code>python c:\python27\scripts\gcovr -g --object-directory=. -r ..\..\..\ --html --html-details -o program.html -v
  </code></pre>
  
  <p>I tried Python36:</p>
  
  <pre><code>c:\python36\scripts\gcovr --use-gcov-files -v --object-dir=.
  </code></pre>
  
  <p>But never get the coverage for my device under test. Only gcov without gcovr works, so the files must be correct.</p>