From 805c7606a0ba910c8e04a4d95b98df02b59b1feb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Franz=20P=C3=B6schel?= <franz.poeschel@gmail.com>
Date: Mon, 22 Apr 2024 15:14:51 +0200
Subject: [PATCH] Print a hint on what might be wrong when retrieveSeries fails
 (#1610)

* Print a hint on what might be wrong when retrieveSeries fails

* add parentheses
---
 src/backend/Attributable.cpp | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/src/backend/Attributable.cpp b/src/backend/Attributable.cpp
index 2388b1726d..c50ca5345d 100644
--- a/src/backend/Attributable.cpp
+++ b/src/backend/Attributable.cpp
@@ -29,6 +29,7 @@
 #include <iostream>
 #include <set>
 #include <sstream>
+#include <stdexcept>
 
 namespace openPMD
 {
@@ -126,8 +127,17 @@ Series Attributable::retrieveSeries() const
     {
         findSeries = findSeries->parent;
     }
-    auto seriesData = &auxiliary::deref_dynamic_cast<internal::SeriesData>(
-        findSeries->attributable);
+    auto *seriesData =
+        dynamic_cast<internal::SeriesData *>(findSeries->attributable);
+    if (!seriesData)
+    {
+        throw std::runtime_error(
+            "[Attributable::retrieveSeries] Error when trying to retrieve the "
+            "Series object. Note: An instance of the Series object must still "
+            "exist when flushing. A common cause for this error is using a "
+            "flush call on a handle (e.g. `Iteration::seriesFlush()`) when the "
+            "original Series object has already gone out of scope.");
+    }
     Series res;
     res.setData(
         std::shared_ptr<internal::SeriesData>{seriesData, [](auto const *) {}});