From 89e3b93c580bd833297316bc04c614cf294ae8eb Mon Sep 17 00:00:00 2001
From: Arnaud Giersch <arnaud.giersch@univ-fcomte.fr>
Date: Thu, 3 Jun 2021 15:34:01 +0200
Subject: [PATCH] Ensure correct ordering of the accumulate requests.

---
 src/smpi/mpi/smpi_win.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/smpi/mpi/smpi_win.cpp b/src/smpi/mpi/smpi_win.cpp
index bd2d17d2bd..8eebb2118b 100644
--- a/src/smpi/mpi/smpi_win.cpp
+++ b/src/smpi/mpi/smpi_win.cpp
@@ -337,6 +337,9 @@ int Win::accumulate(const void *origin_addr, int origin_count, MPI_Datatype orig
     mut_->unlock();
   }
 
+  // FIXME: The current implementation fails to ensure the correct ordering of the accumulate requests.  The following
+  // 'flush' is a workaround to fix that.
+  flush(target_rank);
   XBT_DEBUG("Leaving MPI_Win_Accumulate");
   return MPI_SUCCESS;
 }
-- 
2.20.1