To: J3                                                     J3/25-123
From: Jeff Larkin
Subject: OpenACC Liaison Report
Date: 2025-February-18

#Reference:

OpenACC Liaison Report
======================
Information about OpenACC, including the current standard document,
training materials, and upcoming events can be found at
http://www.openacc.org/.

The current OpenACC standard is version 3.3. Version 3.3 of the OpenACC
specification was adopted November 2022.  The specification can be found
at https://www.openacc.org/specification.

Technical Report 24-1 was released at SC24 in November 2024 as a draft
release of version 3.4. The organization is seeking feedback on this
technical report before finalizing the next release, expected in
early 2025.

News
----
OpenACC continues to be supported by the NVIDIA, HPE/Cray, and GNU
Fortran compilers at various supported versions.

Work is on-going on support for OpenACC in the LLVM/Flang compiler.

Technical Report 24-1 contains a variety of clarifications as well
as a few new features:
* Always modifiers to force the transfer of data between discrete
  memories, even if present behavior would normally result in the
  data to not be copied.
* Capture clause on certain data clauses to declare that discrete
  memory should be used for a given variable, even if the original
  data structure is in unified memory.
* Added the `if` clause on atomic constructs

The committee is seeking feedback on the capture modifier before
releasing the final specification. This modifier came about to
help codes that wish to return asynchronously from a routine,
but have stack data that would be problematic when the stack
is shared between host and device. The NVIDIA HPC SDK contains
a reference implementation of the feature in preview.

Applications
------------
OpenACC adoption remains strong among science applications.

More information on these can be found on the OpenACC
web site at https://www.openacc.org/success-stories.

Community Engagement
--------------------
The OpenACC organization had its annual BOF at SC24 and also
sponsored the Open Accelerated Computing Summit (OACS) in 2024.

The OpenACC slack remain a vibrant community.

Hackathons
----------
OpenACC continues to host numerous hackathons each year. OpenACC is
generally the preferred approach for Fortran applications attending
the events. Event dates are posted at
https://www.openhackathons.org. It is not a requirement to use
OpenACC directives to participate in these hackathons.