From 827bfa45299b826926cd565f97f540301bccccf7 Mon Sep 17 00:00:00 2001
From: Seunghwa Kang <seunghwak@nvidia.com>
Date: Wed, 4 Oct 2023 12:07:52 -0700
Subject: [PATCH] tweak the implementation to silence the spurious warning

---
 ...v_transform_reduce_incoming_outgoing_e.cuh | 28 ++++++++-----------
 1 file changed, 12 insertions(+), 16 deletions(-)

diff --git a/cpp/src/prims/per_v_transform_reduce_incoming_outgoing_e.cuh b/cpp/src/prims/per_v_transform_reduce_incoming_outgoing_e.cuh
index 1349454f5b6..cfba8a35cc1 100644
--- a/cpp/src/prims/per_v_transform_reduce_incoming_outgoing_e.cuh
+++ b/cpp/src/prims/per_v_transform_reduce_incoming_outgoing_e.cuh
@@ -513,24 +513,20 @@ void per_v_transform_reduce_e(raft::handle_t const& handle,
 
   static_assert(is_arithmetic_or_thrust_tuple_of_arithmetic<T>::value);
 
-  [[maybe_unused]] std::conditional_t<GraphViewType::is_storage_transposed,
-                                      edge_src_property_t<GraphViewType, T>,
-                                      edge_dst_property_t<GraphViewType, T>>
-    minor_tmp_buffer(handle);  // relevant only when (GraphViewType::is_multi_gpu && !update_major
+  using minor_tmp_buffer_type = std::conditional_t<GraphViewType::is_storage_transposed,
+                                                   edge_src_property_t<GraphViewType, T>,
+                                                   edge_dst_property_t<GraphViewType, T>>;
+  std::unique_ptr<minor_tmp_buffer_type> minor_tmp_buffer{};
   if constexpr (GraphViewType::is_multi_gpu && !update_major) {
-    if constexpr (GraphViewType::is_storage_transposed) {
-      minor_tmp_buffer = edge_src_property_t<GraphViewType, T>(handle, graph_view);
-    } else {
-      minor_tmp_buffer = edge_dst_property_t<GraphViewType, T>(handle, graph_view);
-    }
+    minor_tmp_buffer = std::make_unique<minor_tmp_buffer_type>(handle, graph_view);
   }
 
   using edge_partition_minor_output_device_view_t =
-    std::conditional_t<update_major,
-                       void /* dummy */,
+    std::conditional_t<GraphViewType::is_multi_gpu && !update_major,
                        detail::edge_partition_endpoint_property_device_view_t<
                          vertex_t,
-                         decltype(minor_tmp_buffer.mutable_view().value_first())>>;
+                         decltype(minor_tmp_buffer->mutable_view().value_first())>,
+                       void /* dummy */>;
 
   if constexpr (update_major) {
     size_t partition_idx = 0;
@@ -549,7 +545,7 @@ void per_v_transform_reduce_e(raft::handle_t const& handle,
   } else {
     if constexpr (GraphViewType::is_multi_gpu) {
       auto minor_init = init;
-      auto view       = minor_tmp_buffer.view();
+      auto view       = minor_tmp_buffer->view();
       if (view.keys()) {  // defer applying the initial value to the end as minor_tmp_buffer may not
                           // store values for the entire minor range
         minor_init = ReduceOp::identity_element;
@@ -558,7 +554,7 @@ void per_v_transform_reduce_e(raft::handle_t const& handle,
         auto const major_comm_rank = major_comm.get_rank();
         minor_init                 = (major_comm_rank == 0) ? init : ReduceOp::identity_element;
       }
-      fill_edge_minor_property(handle, graph_view, minor_init, minor_tmp_buffer.mutable_view());
+      fill_edge_minor_property(handle, graph_view, minor_init, minor_tmp_buffer->mutable_view());
     } else {
       thrust::fill(handle.get_thrust_policy(),
                    vertex_value_output_first,
@@ -699,7 +695,7 @@ void per_v_transform_reduce_e(raft::handle_t const& handle,
       if constexpr (update_major) {
         output_buffer = major_buffer_first;
       } else {
-        output_buffer = edge_partition_minor_output_device_view_t(minor_tmp_buffer.mutable_view());
+        output_buffer = edge_partition_minor_output_device_view_t(minor_tmp_buffer->mutable_view());
       }
     } else {
       output_buffer = vertex_value_output_first;
@@ -913,7 +909,7 @@ void per_v_transform_reduce_e(raft::handle_t const& handle,
     auto const minor_comm_rank = minor_comm.get_rank();
     auto const minor_comm_size = minor_comm.get_size();
 
-    auto view = minor_tmp_buffer.view();
+    auto view = minor_tmp_buffer->view();
     if (view.keys()) {  // applying the initial value is deferred to here
       vertex_t max_vertex_partition_size{0};
       for (int i = 0; i < major_comm_size; ++i) {