YAXT

• potential integer overflow in stripe overlap computation was fully eliminated
• interfaces (xt_xmap_reorder, xt_xmap_update_positions, xt_xmap_spread) to tune/extend the xmap message element sequence for improved memory access patterns
• make the build much cleaner
• improved support for recent PGI compiler releases
• much improved support for various Cray compiler versions
• tons of smaller tweaks/improvements/fixes, see revision log commit:652f8312be016820 for details

• contains a work-around for automake prior to 1.16 spurious file creation (no breakage)
• improves on build-workarounds for NAG Fortran
• improves libtool interaction with PGI compilers when invoked through a wrapper like mpicc
• adds a workaround for a Cray CCE code generation bug, where the compiler makes incorrect assumptions about pointer alignment.

• adds a file missing from the distribution archive (but is only needed when time-stamps get changed)
• fixes a problem when ifort or icc was used with the -diag-disable option having an argument as next command-line argument instead of separated by an equals sign
• fixes needed if autoreconf is performed with automake 1.16

• support for asynchronous exchanges (like MPI_Isend) and
• fixes for MPI implementations where MPI_Pack_size returns an actual upper bound and not the exact amount that MPI_Pack advances position by
• document the consequences segmented memory architectures might have

• User-defined redists via the xt_redist_single_array_base_new function
• Lots of minor cleanup and bug-fixing

• Improved g95 support.
• A memory free bug when concatenating empty redists.
• A minor bug fix for stripe overlap computation when stripe starts are far apart and stride is large.
• New constructor xt_redist_repeat_asym_new allows for different displacements in source and destination arrays.
• Various minor fixes to tests.

• The C part is now available as a separate library so that the differences in linking between Fortran and C can properly be accounted for.
• As a consequence of the above, friendlier generic interfaces are available for Fortran and mpif.h is no longer needed for building YAXT.
• Intercommunicators are supported for constructing Xmaps (destination indices can only be satisified from sources in the remote group) for both, xt_xmap_all2all_new and xt_xmap_dist_dir_new.
• Correctness and performance have been improved for index stripe lists (xt_idxstripes_new) and the distributed-directory based Xmap construction.
• Various internal and test-suite improvements.

In summary the changes are:

• Better support for BlueGene/Q and cross-compilation.
• Copy constructors for xmaps and redists.
• Support for overlapping redist repeat constituents.
• Stricter declaration of some API functions (added const).
• 2 edge cases in stripe overlap got fixed.
• The tests got improved in numerous little places.
• Internal memory allocations have slightly less overhead.

This release fixes the prevention of unnecessary duplication of MPI communicators from 0.4.2 to finally work in all cases.

This release contains a fix to prevent unnecessary duplication of MPI communicators.
Also, another example is added. It shows how to use yaxt for halo exchange of unstructured grid models.