+SimGrid (3.25.1) UNRELEASED (target: March 20 2020 or v3.26 on 3/26/20)
+
+Important user-visible changes:
+ - Surf precision default value is now 1e-9, instead of 1e-5. This was changed as
+ several users had difficult to understand issues when using high bandwidth or
+ small latency events. The new value was already the default for SMPI and
+ should not cause too much performance hit. It can change some simulation
+ timings if simulation was skipping a lot of small events (which was actually
+ an issue of said simulation). The value can still be changed back using
+ --cfg=surf/precision:1e-5.
+ - On some network models (L07, CM02, LV08), an implicit loopback link is created
+ for local communication. Default bandwidth was 500MBps and latency was 15µs,
+ which was rather bad. Default values have been changed to 10GBps and 0 latency.
+ Options network/loopback-lat and network/loopback-bw have been added to adapt
+ these values if needed. Network and routing models already providing separate
+ loopbacks (clusters and such) are not impacted by this change.
+ - SMPI now adds 16 bytes of header to each message sent, in order to simulate
+ metadata that are added to each MPI message by MPI libraries (tag,
+ src/dest, and communicator information). This may change simulation times
+ for very small message sizes, but should be more realistic.
+
+S4U:
+ - the on_exit() of each actor is also executed when the simulation deadlocks.
+
+SMPI:
+ - Update proxy apps coverage of new ECP apps: 60+ apps now tested nightly on
+ https://framagit.org/simgrid/SMPI-proxy-apps
+ - MPI/IO: supports names starting with "./"
+ - Fortran: many MPI/IO bindings, support for MPI_UB/LB, C MPI_INT/FLOAT/DOUBLE
+ datatypes.
+ - smpicc/cxx/ff/f90 now will actually perform definition checks at link time. When
+ building shared libraries, this may cause issues, so environment variable
+ SMPI_NO_UNDEFINED_CHECK can be added to disable this.
+
+C binding:
+ - The return type of the sg_actor_on_exit() callbacks is now 'void'
+ (int value was previously ignored)
+
+General:
+ - LTO is now enabled for Intel/clang compilers.
+ - LTO behavior on GCC can be parameterized using LTO_EXTRA_FLAG in cmake.
+ Setting it to "auto" will use all available cores, while setting it to n will
+ use n cores to speedup link step (usage: cmake -DLTO_EXTRA_FLAG=4).
+
+C interface:
+ - Many MSG tests were converted to the new S4U's interface in C, that
+ was extended for that.
+
+Simix:
+ - Remove obsolete option --cfg=contexts/parallel-threshold.
+
+Fixed bugs (FG#.. -> FramaGit bugs; FG!.. -> FG merge requests)
+ (FG: issues on Framagit; GF: issues on GForge; GH: issues on GitHub)
+ - FG#41: Add sg_actor_create C interface
+ - FG#43: xbt::random needs some care
+ - FG#48: The Impossible Did Happen (yet again)
+ - FG#50: Suspending an actor executed at the current timestamp fails
+ - FG!24: Documentation and fix for xbt/random
+ - FG!35: Add a modeling hint for parallel links in doc
+ - FG!36: [xbt/random] Read/Write the state of the RNG
+ - GF#18137: Allow different stack sizes?
+ - GH#128: Parallelization of simulation with --cfg=contexts/nthreads
+ - GH#139: Allow pthread creation in SMPI
+ - GH#336: Packet-level simulation using SMPI?
+ - GH#346: [SMPI] error while loading shared libraries: libsimgrid.so
+ - GH!337: Fix link_energy plugin for wifi platforms
+ - GH!339: Add Mailbox set_receiver method to python binding
+
+----------------------------------------------------------------------------
+
+SimGrid (3.25) February 2. 2020 (aka 02 02 2020)
+
+The Palindrom Day Release.
+
+Important user-visible changes:
+ - Improve the Python usability (stability and documentation).
+ - A nasty synchronization bug was ironed out, see also below.
+ - Python's doc was organized as a separate tree, now integrated with C++.
+ - C bindings of S4U were not part of the doc.
+ - The C++ doc was also improved as methods are now split by theme.
+ - Further deprecate MSG: you now have to pass -Denable_msg=ON to cmake.
+ - This is mandatory to use the Java bindings.
+ - OFF by default; The plan is to completely remove MSG by 2020Q4 or 2021Q1.
+ - SimDAG++: Automatic dependencies on S4U activities (experimental)
+ - Some features are already implemented but not all of them
+ - Cannot block an activity until it's scheduled on a resource
+ - No heterogeneous wait_any() that would mix Exec/Comm/Io activities.
+ - See examples/s4u/{io,exec,comm}-dependent for what's already there.