From cd61a1d506c30bbb7c1d69da8fae752183a5b1b5 Mon Sep 17 00:00:00 2001
From: Marcel Koch <marcel.koch@kit.edu>
Date: Thu, 21 Apr 2022 09:49:56 +0200
Subject: [PATCH] add communicator size check to copy/move assignment

---
 core/distributed/matrix.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/core/distributed/matrix.cpp b/core/distributed/matrix.cpp
index 98d86bd87a6..55971ff4b6f 100644
--- a/core/distributed/matrix.cpp
+++ b/core/distributed/matrix.cpp
@@ -357,6 +357,8 @@ Matrix<ValueType, LocalIndexType, GlobalIndexType>::operator=(
     const Matrix& other)
 {
     if (this != &other) {
+        GKO_ASSERT_EQ(other.get_communicator().size(),
+                      this->get_communicator().size());
         this->set_size(other.get_size());
         diag_mtx_->copy_from(other.diag_mtx_.get());
         offdiag_mtx_->copy_from(other.offdiag_mtx_.get());
@@ -380,6 +382,8 @@ Matrix<ValueType, LocalIndexType, GlobalIndexType>::operator=(
     Matrix&& other) noexcept
 {
     if (this != &other) {
+        GKO_ASSERT_EQ(other.get_communicator().size(),
+                      this->get_communicator().size());
         this->set_size(other.get_size());
         other.set_size({});
         diag_mtx_->move_from(other.diag_mtx_.get());