+ * Add new macros with variable number of arguments.
+ - in xbt/log.h: XBT_DEBUG, XBT_VERB, XBT_INFO, etc.
+ - in xbt/asserts.h: xbt_assert
+ - in xbt/cunit.h: xbt_test_{add,fail,assert,log}
+ - in xbt/ex.h: THROWF and RETHROWF.
+ Define XBT_USE_DEPRECATED if you want to use the old numbered macros like
+ INFO1, INFO2, etc.
+ * Change xbt_die() to accept a format string with arguments, just like printf.
+ * New data structure: xbt_lib_t, like a dict but more general and with better
+ memory handling.
+
+ INSTR
+ * New configuration options
+ Options triva/categorized and triva/uncategorized can be used to generate
+ graph configuration files for Triva visualization tool.
+ * Configuration option tracing/platform is renamed to tracing/categorized
+ * XBT logging makes tracing error checks easier, new root log hierarchy: instr
+ * New TRACE_user_link_variable interface:
+ User provides the name of the link and the tracing variable to attach to it
+ * the declaration of tracing categories must be done after the environment
+ creation
+ * simpler tracing interface, just one way to declare categories
+ TRACE_category or TRACE_category_with_color, it is up to you
+ * links in the trace file are again identified by their names
+ * trace contains the full platform hierarchy exactly as declared using the ASes
+ * Options tracing/msg/[task|process]:1 groups the process by hosts
+ for both cases, tasks and processes must have names that are unique during the simulation
+ these options generate traces that are suited to gantt-charts, such as the space-time view of Paje
+ * The experimental option tracing/msg/volume is deprecated
+ its functionality may be reincorporated if needed
+ * Buffering
+ The tracing generates a trace file with unordered timestamped events,
+ because of the way the core simulator (surf) works. A script available
+ at the tools directory (fix-paje-trace.sh) can be used to put the events
+ in order. We have changed the tracing so it can generate ordered timestamped
+ events in the final trace, but depending on the simulator (and how much time
+ is simulated) that can lead to a huge memory utilization. It is desactivated
+ by default, but it can be activated using the --cfg=tracing/buffer:1 switch.
+
+ Build Infrastructure
+ * Define a SIMGRID_VERSION macro in simgrid_config.h.
+ - We are trying hard to keep the API stable, but it may happen that
+ some things change (we're a research project after all, not a
+ nuclear plant operating system). If such things should happen, you
+ could rely on that macro to adapt.
+ - current value: 30600 for 3.06.00, aka 3.6
+ * Define macro MAKE_SIMGRID_VERSION(major, minor, patch) to help building
+ a number that can be compared with SIMGRID_VERSION.
+ * Add a build option -Denable_debug (set to ON by default): when set to OFF,
+ assertions and verbose/debug logging events are disabled at compile time.