diff --git a/include/openPMD/auxiliary/DerefDynamicCast.hpp b/include/openPMD/auxiliary/DerefDynamicCast.hpp
index 6b2674ae9e..ecbf2033e1 100644
--- a/include/openPMD/auxiliary/DerefDynamicCast.hpp
+++ b/include/openPMD/auxiliary/DerefDynamicCast.hpp
@@ -22,6 +22,7 @@
 
 #include <optional>
 #include <stdexcept>
+#include <typeinfo>
 
 namespace openPMD
 {
@@ -64,10 +65,17 @@ namespace auxiliary
     inline std::optional<New_Type *>
     dynamic_cast_optional(Old_Type *ptr) noexcept
     {
-        auto const tmp_ptr = dynamic_cast<New_Type *>(ptr);
-        if (tmp_ptr == nullptr)
+        try
+        {
+            auto const tmp_ptr = dynamic_cast<New_Type *>(ptr);
+            if (tmp_ptr == nullptr)
+                return std::nullopt;
+            return {tmp_ptr};
+        }
+        catch (std::bad_cast const &)
+        {
             return std::nullopt;
-        return {tmp_ptr};
+        }
     }
 
 } // namespace auxiliary
diff --git a/src/Mesh.cpp b/src/Mesh.cpp
index d3317070ae..e86283e8c8 100644
--- a/src/Mesh.cpp
+++ b/src/Mesh.cpp
@@ -264,7 +264,7 @@ namespace
     {
         for (auto [unit, exponent] : udim)
         {
-            *(it + static_cast<uint8_t>(unit)) = exponent;
+            it[static_cast<uint8_t>(unit)] = exponent;
         }
     }
 } // namespace