MPICH 4.2.1 released

A new stable release of MPICH, 4.2.1, is now available for download. This is the first bug-fix release in the 4.2.x series. This release addresses a number of user-reported crashes and build issues. It can be found on our downloads page. For the full set of commits see https://github.com/pmodels/mpich/compare/v4.2.0…v4.2.1/

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                       Changes in 4.2.1
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# Disable flat_namespace to build libmpifort on macOS by default

# Prefix warning messages with "MPICH"

# Add --disable-doc configure option

# Fix support for building MPICH Fortran support with Xcode 15 on macOS

# Fix bug in MPI_WIN_SHARED_QUERY when window is not shared

# Fix bug in ch4/ofi gpu pipelining

# Fixes for Intel GPU support

# Fix memory leak in ch4/shm collectives

# Fix bug in MPI_COMM_SPLIT with intercommunicators and non-zero root

# Fix bug in DAOS ROMIO driver

# Fix bug in cycling error code array

# Return an error if there is failure to create a datatype in mpi_f08
module for noncontiguous user data

# Return an error when shared memory segment creation fails