From cf8d9f8e233be2ac68aeb65a95e992adfb483939 Mon Sep 17 00:00:00 2001
From: Weiqun Zhang <WeiqunZhang@lbl.gov>
Date: Mon, 31 Jul 2023 08:55:32 -0700
Subject: [PATCH] Fix a bug in AmrMesh::ChopGrids (#3460)

Fix a corner case for AmrMesh::ChopGrids when there is only one cell in
one dimension.

Close #3459
---
 Src/AmrCore/AMReX_AmrMesh.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Src/AmrCore/AMReX_AmrMesh.cpp b/Src/AmrCore/AMReX_AmrMesh.cpp
index a67e025a38e..46124fee39d 100644
--- a/Src/AmrCore/AMReX_AmrMesh.cpp
+++ b/Src/AmrCore/AMReX_AmrMesh.cpp
@@ -457,7 +457,9 @@ AmrMesh::ChopGrids (int lev, BoxArray& ba, int target_size) const
             int idim = chunk_dir[idx].second;
             if (refine_grid_layout_dims[idim]) {
                 int new_chunk_size = chunk[idim] / 2;
-                if (new_chunk_size%blocking_factor[lev][idim] == 0) {
+                if (new_chunk_size != 0 &&
+                    new_chunk_size%blocking_factor[lev][idim] == 0)
+                {
                     chunk[idim] = new_chunk_size;
                     ba.maxSize(chunk);
                     break;