MPC_4.4.0

[4.4.0] - 2026-08-04

Added

• Rail Portals
  • Added BXI version 3 support
• Low Comm
  • New lowcomm top level one sided communication interface
• OpenSHMEM
  • New network module based on a subpart of the OpenSHMEM specification

Changed

• MPI
  • Added MPI 4.1 errors
• Low Comm
  • Unify Lowcomm API using sendmode preparing integration of UBCL component

Fixed

• Low Comm
  • LCP active message rendezvous container memory leak
  • Finish the implementation of the various types of flush
  • CMA support test between processes leading to more communications going though CMA
  • Atomics with double precision floating point numbers
  • Synchronize host and NIC memory in Portals flushes
• MPI
  • Compute the correct inclusive UB for predefined datatypes
  • Handle NULL MPI_Info duplication
  • Comm_split special case: duplicate the communicator when only one color instead of referencing it
• OpenMP
  • Fix omp_get_max_threads to give a lower bound estimation with respect to topology when in hybrid MPI/OpenMP mode.

MPC_4.3.1

[4.3.1] - 2026-04-08

Added

• Common
  • Debug assertion in the mempool to detect bad behavior
• LowComm
  • Support for floating point numbers in atomic operations

Changed

• Build
  • Enable process-mode by default when using installmpc
  • Search SLURM as default launcher in installmpc and fallback to Hydra if not found
• Chore
  • Default branch to main (devel and master will not be updated)
  • Refactor Documentation and deployment through GitHub pages
• LowComm
  • Avoid warnings in CPP by changing header inclusion rules
  • Improve selection of the network devices to initialize
  • Generate and use unique tags for internal communications (avoiding incorrect matches)
• MPCRUN
  • Optimize launching time by removing one mpc_print_config invocation
• Pthread
  • Avoid redefinition of standard libc symbols in process-mode

Fixed

• Build
  • Export missing build necessary files in the archive
• Common
  • Set visibility attributes of user main to default
• Fortran
  • Non standard code generation
  • Properly convert MPI NULL handles and indexes from C
• MPI
  • Active Message handling in Thread-Based
  • Unpacking of user created datatypes
  • Deadlock in MPI_Waitall in Thread-Based
  • Possible double frees in Window creation and freeing
  • Add missing qualifiers and Fortran constants to the exported API
• Low Comm
  • Multinic devices initialization
  • Interface capabilities initialization
  • Deadlock in backend releasing
  • Deadlock in flush operation with no pending communications
  • Potential error in PTL finalization in multithreaded context
  • Rendezvous Active Message user headers not reaching the target
  • Release the PTL backend in the right order
• Memory related potential bugs in MPI, Low Comm, Common and Config

MPC_4.3.0

[4.3.0] - 2025-11-18

Added

• Accelerators
  • Support CUDA
  • Support HIP
• Build
  • Add release with debug information optimization option (--relwithdebinfo)
• Low Comm / RED-SEA Project
  • Refactoring LCP module to better support suit protocols evolutions
  • Support for implementing protocols on top of rails (active message)
  • Support for multirail and fragmentation
  • Extension of rail API to support stream-like data transfers (tcp and ptl only)
  • Component-based transport with static loading
• MPI
  • Support Gather Allgather Bcast topological collectives
  • Support for MPI Tools interface

Changed

• Compilers
  • Activate privatization only if the underlying compiler is capable
• OMP
  • Enhancing support of OpenMP task and interactions with MPI
• MPCRUN
  • Change default count for resource request

Removed

• Low Comm
  • Remove deprecated Portals compatibility layer
• Threads
  • Remove NG scheduler used for research purposes

Deprecated

• Threads
  • Workshare support (needs GCC 7.3 to work)

Fixed

• Build
  • Add support for GCC 13, 14, 15 and C23
  • Fix --enable-debug-mem by correctly depending on libasan
• Compilers
  • Fix compilers wrong error code propagation
  • Fix wrong linking option with fortran in process mode
• Launch
  • Fix PMIx inter-node intra-node initialization
  • Add missing calls to PMIx_Finalize
  • Fix wrong termination with PMIx on abortion
• Low Comm
  • Fix PTL RMA completion system
  • Fix PTL RMA Flush operations
  • Fix LCP atomics
• MPI
  • Fix Exscan algorithm selection
  • Fix Pack and Unpack capabilities
  • Fix MPI_Self path
  • Accept NULL as bypass for MPI_T query functions
  • Fix persistent communications request initialization
  • Plenty of small bug fixes in all parts of MPC

bxiv3 simulator compatibility

bxiv3_simulator_compatibility

Fixe: MPCOpenMP linking against system OpenMP leading to segv