From 52f017d8a1042f78e97778bd4da8c3d2ca7a3041 Mon Sep 17 00:00:00 2001
From: Stan Moore <stamoor@sandia.gov>
Date: Wed, 14 Mar 2018 10:41:12 -0600
Subject: [PATCH] Fix MPI overlapping buffer issue

---
 src/comm_types/comm_mpi.cpp | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/comm_types/comm_mpi.cpp b/src/comm_types/comm_mpi.cpp
index 27562ca..45628df 100644
--- a/src/comm_types/comm_mpi.cpp
+++ b/src/comm_types/comm_mpi.cpp
@@ -149,44 +149,44 @@ void CommMPI::create_domain_decomposition() {
 
 void CommMPI::scan_int(T_INT* vals, T_INT count) {
   if(std::is_same<T_INT,int>::value) {
-    MPI_Scan(vals,vals,count,MPI_INT,MPI_SUM,MPI_COMM_WORLD);
+    MPI_Scan(MPI_IN_PLACE,vals,count,MPI_INT,MPI_SUM,MPI_COMM_WORLD);
   }
 }
 
 void CommMPI::reduce_int(T_INT* vals, T_INT count) {
   if(std::is_same<T_INT,int>::value) {
-    MPI_Allreduce(vals,vals,count,MPI_INT,MPI_SUM,MPI_COMM_WORLD);
+    MPI_Allreduce(MPI_IN_PLACE,vals,count,MPI_INT,MPI_SUM,MPI_COMM_WORLD);
   }
 }
 
 void CommMPI::reduce_float(T_FLOAT* vals, T_INT count) {
   if(std::is_same<T_FLOAT,double>::value) {
     // This generates MPI_ERR_BUFFER for count>1
-    MPI_Allreduce(vals,vals,count,MPI_DOUBLE,MPI_SUM,MPI_COMM_WORLD);
+    MPI_Allreduce(MPI_IN_PLACE,vals,count,MPI_DOUBLE,MPI_SUM,MPI_COMM_WORLD);
   }
 }
 
 void CommMPI::reduce_max_int(T_INT* vals, T_INT count) {
   if(std::is_same<T_INT,int>::value) {
-    MPI_Allreduce(vals,vals,count,MPI_INT,MPI_MAX,MPI_COMM_WORLD);
+    MPI_Allreduce(MPI_IN_PLACE,vals,count,MPI_INT,MPI_MAX,MPI_COMM_WORLD);
   }
 }
 
 void CommMPI::reduce_max_float(T_FLOAT* vals, T_INT count) {
   if(std::is_same<T_FLOAT,double>::value) {
-    MPI_Allreduce(vals,vals,count,MPI_DOUBLE,MPI_MAX,MPI_COMM_WORLD);
+    MPI_Allreduce(MPI_IN_PLACE,vals,count,MPI_DOUBLE,MPI_MAX,MPI_COMM_WORLD);
   }
 }
 
 void CommMPI::reduce_min_int(T_INT* vals, T_INT count) {
   if(std::is_same<T_INT,int>::value) {
-    MPI_Allreduce(vals,vals,count,MPI_INT,MPI_MAX,MPI_COMM_WORLD);
+    MPI_Allreduce(MPI_IN_PLACE,vals,count,MPI_INT,MPI_MAX,MPI_COMM_WORLD);
   }
 }
 
 void CommMPI::reduce_min_float(T_FLOAT* vals, T_INT count) {
   if(std::is_same<T_FLOAT,double>::value) {
-    MPI_Allreduce(vals,vals,count,MPI_DOUBLE,MPI_MAX,MPI_COMM_WORLD);
+    MPI_Allreduce(MPI_IN_PLACE,vals,count,MPI_DOUBLE,MPI_MAX,MPI_COMM_WORLD);
   }
 }