From d5c9c14f636cbf4451af9ad6a29045415fc3d7de Mon Sep 17 00:00:00 2001
From: Benjamin Kietzman <bengilgit@gmail.com>
Date: Wed, 22 May 2019 11:06:26 -0400
Subject: [PATCH] use checked_cast

---
 cpp/src/arrow/compute/kernels/mask.cc | 10 ++++++----
 cpp/src/arrow/compute/kernels/take.cc | 10 ++++++----
 2 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/cpp/src/arrow/compute/kernels/mask.cc b/cpp/src/arrow/compute/kernels/mask.cc
index 472c50af9dfa1..2aaa9a9a622e1 100644
--- a/cpp/src/arrow/compute/kernels/mask.cc
+++ b/cpp/src/arrow/compute/kernels/mask.cc
@@ -30,6 +30,8 @@
 namespace arrow {
 namespace compute {
 
+using internal::checked_cast;
+
 Status Mask(FunctionContext* context, const Array& values, const Array& mask,
             std::shared_ptr<Array>* out) {
   Datum out_datum;
@@ -135,18 +137,18 @@ struct UnpackValues {
   template <typename ValueType>
   Status Visit(const ValueType&) {
     using OutBuilder = typename TypeTraits<ValueType>::BuilderType;
-    auto&& mask = static_cast<const ArrayType<MaskType>&>(*params_.mask);
-    auto&& values = static_cast<const ArrayType<ValueType>&>(*params_.values);
+    const auto& mask = checked_cast<const ArrayType<MaskType>&>(*params_.mask);
+    const auto& values = checked_cast<const ArrayType<ValueType>&>(*params_.values);
     std::unique_ptr<ArrayBuilder> builder;
     RETURN_NOT_OK(MakeBuilder(params_.context->memory_pool(), values.type(), &builder));
     RETURN_NOT_OK(builder->Reserve(OutputSize(mask)));
     RETURN_NOT_OK(UnpackValuesNullCount(params_.context, values, mask,
-                                        static_cast<OutBuilder*>(builder.get())));
+                                        checked_cast<OutBuilder*>(builder.get())));
     return builder->Finish(params_.out);
   }
 
   Status Visit(const NullType& t) {
-    auto&& mask = static_cast<const ArrayType<MaskType>&>(*params_.mask);
+    const auto& mask = checked_cast<const ArrayType<MaskType>&>(*params_.mask);
     params_.out->reset(new NullArray(OutputSize(mask)));
     return Status::OK();
   }
diff --git a/cpp/src/arrow/compute/kernels/take.cc b/cpp/src/arrow/compute/kernels/take.cc
index 6addcd7444ded..b77715abb6ffc 100644
--- a/cpp/src/arrow/compute/kernels/take.cc
+++ b/cpp/src/arrow/compute/kernels/take.cc
@@ -28,6 +28,8 @@
 namespace arrow {
 namespace compute {
 
+using internal::checked_cast;
+
 Status Take(FunctionContext* context, const Array& values, const Array& indices,
             std::shared_ptr<Array>* out) {
   Datum out_datum;
@@ -117,20 +119,20 @@ struct UnpackValues {
   Status Visit(const ValueType&) {
     using ValueArrayRef = const typename TypeTraits<ValueType>::ArrayType&;
     using OutBuilder = typename TypeTraits<ValueType>::BuilderType;
-    IndexArrayRef indices = static_cast<IndexArrayRef>(*params_.indices);
-    ValueArrayRef values = static_cast<ValueArrayRef>(*params_.values);
+    IndexArrayRef indices = checked_cast<IndexArrayRef>(*params_.indices);
+    ValueArrayRef values = checked_cast<ValueArrayRef>(*params_.values);
     std::unique_ptr<ArrayBuilder> builder;
     RETURN_NOT_OK(MakeBuilder(params_.context->memory_pool(), values.type(), &builder));
     RETURN_NOT_OK(builder->Reserve(indices.length()));
     RETURN_NOT_OK(UnpackValuesNullCount(params_.context, values, indices,
-                                        static_cast<OutBuilder*>(builder.get())));
+                                        checked_cast<OutBuilder*>(builder.get())));
     return builder->Finish(params_.out);
   }
 
   Status Visit(const NullType& t) {
     auto indices_length = params_.indices->length();
     if (indices_length != 0) {
-      auto indices = static_cast<IndexArrayRef>(*params_.indices).raw_values();
+      auto indices = checked_cast<IndexArrayRef>(*params_.indices).raw_values();
       auto minmax = std::minmax_element(indices, indices + indices_length);
       auto min = static_cast<int64_t>(*minmax.first);
       auto max = static_cast<int64_t>(*minmax.second);