From 4552388e438f6cb84a734b663f148d4ae68d4ad2 Mon Sep 17 00:00:00 2001
From: AlePalu <alessandropalummo@gmail.com>
Date: Fri, 8 Mar 2024 18:46:27 +0100
Subject: [PATCH] non_owning_storage move semantic, solved pessimizing-move
 warning in binary_matrix

---
 fdaPDE/linear_algebra/binary_matrix.h | 4 ++--
 fdaPDE/utils/type_erasure.h           | 5 +++++
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/fdaPDE/linear_algebra/binary_matrix.h b/fdaPDE/linear_algebra/binary_matrix.h
index d0799e8e..274cf1ac 100644
--- a/fdaPDE/linear_algebra/binary_matrix.h
+++ b/fdaPDE/linear_algebra/binary_matrix.h
@@ -471,7 +471,7 @@ template <int Rows, int Cols, typename XprType> class BinMtxBase {
             for (int j = 0; j < mtx.cols(); ++j) {
                 if (!get().operator()(i, j)) masked_mtx(i, j) = 0;
             }
-        return std::move(masked_mtx);
+        return masked_mtx;
     }
     template <typename ExprType>
     SpMatrix<typename ExprType::Scalar> select(const Eigen::SparseMatrixBase<ExprType>& mtx) const {
@@ -482,7 +482,7 @@ template <int Rows, int Cols, typename XprType> class BinMtxBase {
             for (typename SpMatrix<Scalar_>::InnerIterator it(masked_mtx, k); it; ++it) {
                 if (!get().operator()(it.row(), it.col())) { it.valueRef() = 0; }
             }
-        return std::move(masked_mtx);
+        return masked_mtx;
     }
     // block-repeat operation
     BinMtxBlockRepeatOp<Dynamic, Dynamic, XprType> blk_repeat(int rep_row, int rep_col) const {
diff --git a/fdaPDE/utils/type_erasure.h b/fdaPDE/utils/type_erasure.h
index 36bc4a26..df31584c 100644
--- a/fdaPDE/utils/type_erasure.h
+++ b/fdaPDE/utils/type_erasure.h
@@ -116,6 +116,11 @@ struct non_owning_storage {
         ptr_ = other.ptr_;
         return *this;
     }
+    non_owning_storage(non_owning_storage&& other) : ptr_(std::exchange(other.ptr_, nullptr)) { }
+    non_owning_storage& operator=(non_owning_storage&& other) {
+        ptr_ = std::exchange(other.ptr_, nullptr);
+        return *this;
+    }
 };
 
 struct heap_storage {