\section faq_troubleshooting Troubleshooting
+\subsubsection faq_trouble_changelog The feature X stopped to work after my last update
+
+I guess that you want to read the ChangeLog file, that always contains
+all the information that could be important to the users during the
+upgrade. Actually, you may want to read it (alongside with the NEWS
+file that highlights the most important changes) even before you
+upgrade your copy of SimGrid, too.
+
+Backward compatibility is very important to us, as we want to provide
+a scientific tool allowing to evaluate the code you write in several
+years, too. That being said, we sometimes change the interface to make
+them more usable to the users. When we do so, we always keep the old
+interface as DEPRECATED. If you still want to use them, you want to
+define the SIMGRID_DEPRECATED preprocessor symbol before loading the
+SimGrid files:
+
+@verbatim
+#define SIMGRID_DEPRECATED
+#include <msg/msg.h>
+@endverbatim
+
\subsection faq_trouble_lib_compil SimGrid compilation and installation problems
\subsubsection faq_trouble_lib_config cmake fails!
