From 0c940d1053694e2e6993e0a6c0ef7830dbf3e698 Mon Sep 17 00:00:00 2001
From: Scot Breitenfeld <brtnfld@hdfgroup.org>
Date: Thu, 2 Jul 2026 17:41:34 -0500
Subject: [PATCH] Handle H5T_COMPLEX in generate_random_datatype

HDF5 2.0 (tracked by the develop branch) adds a new datatype class,
H5T_COMPLEX (native complex-number support), bumping H5T_NCLASSES from
11 to 12. generate_random_datatype()'s rand() % H5T_NCLASSES roll had no
case for the new value, falling through to the default "invalid
datatype class" error path and returning an invalid datatype - breaking
every subsequent test in the run that happened to roll a complex type.

Add a case treating it like the other currently-unsupported classes
(H5T_TIME, H5T_BITFIELD, H5T_OPAQUE, H5T_VLEN): retry with a different
random class. Version-gated since H5T_COMPLEX doesn't exist as a symbol
pre-2.0.
---
 vol_test_util.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/vol_test_util.c b/vol_test_util.c
index 106d158..874a820 100644
--- a/vol_test_util.c
+++ b/vol_test_util.c
@@ -166,6 +166,12 @@ generate_random_datatype(H5T_class_t parent_class, hbool_t is_compact)
 
             gen_func = generate_random_datatype_array;
             break;
+#if H5_VERSION_GE(2, 0, 0)
+        case H5T_COMPLEX:
+            /* Complex number datatypes are unsupported, try again */
+            goto roll_datatype;
+            break;
+#endif
         default:
             HDprintf("    invalid datatype class\n");
             goto done;