GROMACS 2019.6 release notes
----------------------------

This version was released on February 28th, 2020. These release notes
document the changes that have taken place in GROMACS since the
previous 2019.5 version, to fix known issues. It also incorporates all
fixes made in version 2018.8 and earlier, which you can find described
in the :ref:`release-notes`.

.. Note to developers!
   Please use """"""" to underline the individual entries for fixed issues in the subfolders,
   otherwise the formatting on the webpage is messed up.
   Also, please use the syntax :issue:`number` to reference issues on GitLab, without the
   a space between the colon and number!

Fixes where mdrun could behave incorrectly
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Actually fix PME forces with FE without perturbed q/LJ
""""""""""""""""""""""""""""""""""""""""""""""""""""""

PME would incorrectly ignore the mesh forces on perturbed atoms when
no charges or LJ atom types were actually perturbed. Note that this
is a rather uncommon scenario.

:issue:`2640`
:issue:`3359`

Avoid overzealous program abort with orientation restraints
"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""

It could happen that mdrun would abort on checking orientation
restraints in multiple molecules even though no restraints where
applied to them.

:issue:`3375`

Calculate Coulomb and LJ reciprocal terms in rerun
""""""""""""""""""""""""""""""""""""""""""""""""""

Reruns would not calculate Coulomb and LJ reciprocal terms, leading
to wrong potential energies. This bug only showed up if GROMACS was
compiled without GPU support.

:issue:`3400`

Fixes for ``gmx`` tools
^^^^^^^^^^^^^^^^^^^^^^^

Added check for inconsistent input of distance restraint labels
in gmx disre.

Fixes that affect portability
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Fix compiler errors with Intel compiler
"""""""""""""""""""""""""""""""""""""""

Fix compiler error with Intel compiler 2019 update 5 and 2020 initial release.
Compilation was failing with ``mcpcom: core dumped`` for the file :file:`pullutil.cpp`.

Miscellaneous
^^^^^^^^^^^^^

Avoid cryptic GPU detection errors when devices are unavailable or out of memory
""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""

:issue:`3178`
:issue:`3399`

