From 31645f3408b41b5f7776c35a0979118e46ed24f0 Mon Sep 17 00:00:00 2001
From: Sean McBride <sean@rogue-research.com>
Date: Mon, 22 Mar 2021 14:16:39 -0400
Subject: [PATCH] Don't treat 2d array as 1d array, fixing UBSan complaint in
 `CPP_testhdf5`

---
 c++/test/ttypes.cpp | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/c++/test/ttypes.cpp b/c++/test/ttypes.cpp
index b6337404ff0..f14e10a48f1 100644
--- a/c++/test/ttypes.cpp
+++ b/c++/test/ttypes.cpp
@@ -656,7 +656,6 @@ static void
 test_named()
 {
     static hsize_t ds_size[2] = {10, 20};
-    hsize_t        i;
     unsigned       attr_data[10][20];
     DataType *     ds_type = NULL;
 
@@ -726,8 +725,11 @@ test_named()
 
         // It should be possible to define an attribute for the named type
         Attribute attr1 = itype.createAttribute("attr1", PredType::NATIVE_UCHAR, space);
-        for (i = 0; i < ds_size[0] * ds_size[1]; i++)
-            attr_data[0][i] = (int)i; /*tricky*/
+        for (hsize_t i = 0; i < ds_size[0]; i++) {
+	        for (hsize_t j = 0; j < ds_size[1]; j++) {
+				attr_data[i][j] = (unsigned)(i * ds_size[1]] + j);
+			}
+        }
         attr1.write(PredType::NATIVE_UINT, attr_data);
         attr1.close();