From 6b6628cbd360e5b281a2af00f3cee46570882f68 Mon Sep 17 00:00:00 2001
From: Landon Owen <lndnwn9@gmail.com>
Date: Mon, 19 Aug 2024 11:42:10 -0700
Subject: [PATCH] Fixed inconsistency in Communicator for non-MPI builds and
 added pointer function to get null pointer for adiak

---
 src/Distributed/Communicator.hh        | 10 +++++++---
 src/PYB11/Utilities/Utilities_PYB11.py |  2 +-
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/src/Distributed/Communicator.hh b/src/Distributed/Communicator.hh
index 11a03fb13..19437d56d 100644
--- a/src/Distributed/Communicator.hh
+++ b/src/Distributed/Communicator.hh
@@ -9,6 +9,8 @@
 
 #ifdef USE_MPI
 #include <mpi.h>
+#else
+typedef int MPI_Comm;
 #endif
 
 namespace Spheral {
@@ -21,18 +23,20 @@ public:
   static Communicator& instance() { static Communicator theInstance; return theInstance; }
 
   // Access the communicator.
-#ifdef USE_MPI
   static MPI_Comm& communicator() { return instance().mCommunicator; }
   static void communicator(MPI_Comm& comm) { instance().mCommunicator = comm; }
+#ifdef USE_MPI
+  static MPI_Comm* comm_ptr() { return &(instance().mCommunicator); }
 #else
-  static int communicator() { return 0; }
-  static void communicator(int&) {}
+  static MPI_Comm* comm_ptr() { return nullptr; }
 #endif
 
 private:
   //------------------------===== Private Interface =====----------------------//
 #ifdef USE_MPI
   MPI_Comm mCommunicator;
+#else
+  MPI_Comm mCommunicator = 0;
 #endif
 
   // No public constructors, destructor, or assignment.
diff --git a/src/PYB11/Utilities/Utilities_PYB11.py b/src/PYB11/Utilities/Utilities_PYB11.py
index 3ef35e9ad..c54a4e894 100644
--- a/src/PYB11/Utilities/Utilities_PYB11.py
+++ b/src/PYB11/Utilities/Utilities_PYB11.py
@@ -68,7 +68,7 @@
 namespace Spheral {
 
 inline void spheral_adiak_init() {
-  adiak::init((void*) Communicator::communicator());
+  adiak::init(Communicator::instance().comm_ptr());
   // Always collect some curated default adiak information
   adiak::adiakversion();
   adiak::user();