From 7f3b333815cf1d515e7d77a1561d83890182d2a4 Mon Sep 17 00:00:00 2001
From: MarkLee131 <kaixuan.li@ntu.edu.sg>
Date: Tue, 7 Apr 2026 00:39:16 +0800
Subject: [PATCH 1/3] fix GetColumnNames() undefined behavior on empty label
 row

GetColumnNames() did .begin() + (mRowNameIdx + 1) on the label row
without checking that the row has enough elements. When the label row
is empty (e.g. after InsertRow on an empty document with LabelParams(0,0)),
.begin() wraps a null pointer and adding to it is undefined behavior.

Add a bounds check before the iterator arithmetic so it returns an
empty vector instead of hitting UB.
---
 src/rapidcsv.h | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/rapidcsv.h b/src/rapidcsv.h
index bc83e0e..53e1f58 100644
--- a/src/rapidcsv.h
+++ b/src/rapidcsv.h
@@ -1473,9 +1473,13 @@ namespace rapidcsv
     {
       if (mLabelParams.mColumnNameIdx >= 0)
       {
-        return std::vector<std::string>(mData.at(static_cast<size_t>(mLabelParams.mColumnNameIdx)).begin() +
-                                        (mLabelParams.mRowNameIdx + 1),
-                                        mData.at(static_cast<size_t>(mLabelParams.mColumnNameIdx)).end());
+        const auto& labelRow = mData.at(static_cast<size_t>(mLabelParams.mColumnNameIdx));
+        const size_t offset = static_cast<size_t>(mLabelParams.mRowNameIdx + 1);
+        if (offset <= labelRow.size())
+        {
+          return std::vector<std::string>(labelRow.begin() + static_cast<int>(offset),
+                                          labelRow.end());
+        }
       }
 
       return std::vector<std::string>();

From 30271a046df03df256dbbfc7be93934a61f5ab88 Mon Sep 17 00:00:00 2001
From: Kristofer Berggren <kristofer.berggren@gmail.com>
Date: Sun, 12 Apr 2026 12:39:47 +0800
Subject: [PATCH 2/3] add test for get column labels of empty label row

---
 CMakeLists.txt    |  1 +
 tests/test107.cpp | 31 +++++++++++++++++++++++++++++++
 2 files changed, 32 insertions(+)
 create mode 100644 tests/test107.cpp

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 31e21ed..b4d1564 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -196,6 +196,7 @@ if(RAPIDCSV_BUILD_TESTS)
   add_unit_test(test104)
   add_unit_test(test105)
   add_unit_test(test106)
+  add_unit_test(test107)
 
   # perf tests
   add_perf_test(ptest001)
diff --git a/tests/test107.cpp b/tests/test107.cpp
new file mode 100644
index 0000000..7114454
--- /dev/null
+++ b/tests/test107.cpp
@@ -0,0 +1,31 @@
+// test107.cpp - get column labels of empty label row
+
+#include <rapidcsv.h>
+#include "unittest.h"
+
+int main()
+{
+  int rv = 0;
+
+  try
+  {
+    // Empty document, specify column and row labels available
+    std::string csv = "";
+    std::istringstream s(csv);
+    rapidcsv::Document doc(s, rapidcsv::LabelParams(0, 0));
+
+    // InsertRow create a row with 0 columns
+    doc.InsertRow<std::string>(0);
+
+    // Get column names
+    std::vector<std::string> names = doc.GetColumnNames();
+    unittest::ExpectEqual(size_t, names.size(), size_t(0));
+  }
+  catch (const std::exception& ex)
+  {
+    std::cout << "exception: " << ex.what() << std::endl;
+    rv = 1;
+  }
+
+  return rv;
+}

From 8335635653d024f3c7ed6341f4b966bb1dc2262f Mon Sep 17 00:00:00 2001
From: Kristofer Berggren <kristofer.berggren@gmail.com>
Date: Sun, 12 Apr 2026 12:46:56 +0800
Subject: [PATCH 3/3] minor code style change, bump version

---
 src/rapidcsv.h | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/src/rapidcsv.h b/src/rapidcsv.h
index 53e1f58..3111db9 100644
--- a/src/rapidcsv.h
+++ b/src/rapidcsv.h
@@ -2,7 +2,7 @@
  * rapidcsv.h
  *
  * URL:      https://github.com/d99kris/rapidcsv
- * Version:  8.95
+ * Version:  8.96
  *
  * Copyright (C) 2017-2026 Kristofer Berggren
  * All rights reserved.
@@ -1473,12 +1473,11 @@ namespace rapidcsv
     {
       if (mLabelParams.mColumnNameIdx >= 0)
       {
-        const auto& labelRow = mData.at(static_cast<size_t>(mLabelParams.mColumnNameIdx));
+        const std::vector<std::string>& labelRow = mData.at(static_cast<size_t>(mLabelParams.mColumnNameIdx));
         const size_t offset = static_cast<size_t>(mLabelParams.mRowNameIdx + 1);
         if (offset <= labelRow.size())
         {
-          return std::vector<std::string>(labelRow.begin() + static_cast<int>(offset),
-                                          labelRow.end());
+          return std::vector<std::string>(labelRow.begin() + static_cast<int>(offset), labelRow.end());
         }
       }