From a1468fd6ec8448de409c3240b51e3a7ae584f36a Mon Sep 17 00:00:00 2001
From: Marco van Hulten <Marco.van.Hulten@uni-bonn.de>
Date: Fri, 15 Aug 2025 11:27:16 +0200
Subject: [PATCH] Set MPI executable for ParFlow

This is needed when GCC+OpenMPI is used.  This is tested on JURECA.

With Intel+ParaStationMPI this already went right; there is no effect when
compiling with Intel LLVM.

Resolves: #87
---
 cmake/BuildParFlow.cmake | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/cmake/BuildParFlow.cmake b/cmake/BuildParFlow.cmake
index 708e14a..d3f9f65 100644
--- a/cmake/BuildParFlow.cmake
+++ b/cmake/BuildParFlow.cmake
@@ -77,8 +77,8 @@ ExternalProject_Add(ParFlow
                 -DPARFLOW_AMPS_SEQUENTIAL_IO=ON
                 -DPARFLOW_ENABLE_TIMING=TRUE
                 -DPARFLOW_ACCELERATOR_BACKEND=${PF_ACC_BACKEND}
-                -DMPIEXEC_EXECUTABLE=${MPIEXEC_EXECUTABLE}
-                -DMPIEXEC_NUMPROC_FLAG=${MPIEXEC_NUMPROC_FLAG}
+                -DMPIEXEC_EXECUTABLE=${SLURM_SRUN}
+                -DMPIEXEC_NUMPROC_FLAG=--ntasks
                 -DPARFLOW_ENABLE_SLURM=${ENABLE_SLURM}
                 ${PF_CLM_FLAGS}
     DEPENDS     ${MODEL_DEPENDENCIES}