From 4517f564229304f3aec5f03b8aca26db5d65e94b Mon Sep 17 00:00:00 2001
From: Pierre Matalon <pierre.matalon@gmail.com>
Date: Mon, 16 Dec 2024 14:41:08 +0100
Subject: [PATCH] static_assert in transfer() with Eigen

---
 include/samurai/reconstruction.hpp      | 4 ++++
 include/samurai/storage/eigen/eigen.hpp | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/include/samurai/reconstruction.hpp b/include/samurai/reconstruction.hpp
index 083697054..f2d1156d3 100644
--- a/include/samurai/reconstruction.hpp
+++ b/include/samurai/reconstruction.hpp
@@ -1102,6 +1102,10 @@ namespace samurai
                             }
                             else
                             {
+#if defined(SAMURAI_FIELD_CONTAINER_EIGEN3)
+                                static_assert(Field_src::is_soa && Field_src::size > 1, "transfer() is not implemented with Eigen for scalar fields and vectorial fields in AOS.");
+                                // In the lid-driven-cavity demo, the following line does not compile with Eigen.
+#endif
                                 view(dst, i_dst) += view(src, static_cast<size_type>(ii)) / (1 << shift * dim);
                             }
                         }
diff --git a/include/samurai/storage/eigen/eigen.hpp b/include/samurai/storage/eigen/eigen.hpp
index fdd7b3ca4..05adf9de5 100644
--- a/include/samurai/storage/eigen/eigen.hpp
+++ b/include/samurai/storage/eigen/eigen.hpp
@@ -276,7 +276,7 @@ namespace samurai
     }
 
     template <class Scalar, int RowsAtCompileTime, int ColsAtCompileTime, int Options, class RowIndices, class ColIndices, class... Ranges>
-    inline auto& view(Eigen::IndexedView<Eigen::Array<Scalar, RowsAtCompileTime, ColsAtCompileTime, Options>, RowIndices, ColIndices>& exp,
+    auto view(Eigen::IndexedView<Eigen::Array<Scalar, RowsAtCompileTime, ColsAtCompileTime, Options>, RowIndices, ColIndices>& exp,
               Ranges... ranges)
     {
         return exp(ranges...);