>From 3ee8ce232478edbe1b93456285b29340fe2eee3e Mon Sep 17 00:00:00 2001
From: Bruno Haible <bruno@clisp.org>
Date: Tue, 5 Nov 2024 21:12:06 +0100
Subject: [PATCH 20/23] wcsncmp tests: Verify N3322 functionality.

* tests/test-wcsncmp.c (main): Add zero-size tests.
---
 ChangeLog            |  5 +++++
 tests/test-wcsncmp.c | 14 ++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index 0bb5d71f79..0efaf7854b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2024-11-05  Bruno Haible  <bruno@clisp.org>
+
+	wcsncmp tests: Verify N3322 functionality.
+	* tests/test-wcsncmp.c (main): Add zero-size tests.
+
 2024-11-05  Bruno Haible  <bruno@clisp.org>
 
 	wcsncat tests: Verify N3322 functionality.
diff --git a/tests/test-wcsncmp.c b/tests/test-wcsncmp.c
index 6db6c248ef..c1fe103ef4 100644
--- a/tests/test-wcsncmp.c
+++ b/tests/test-wcsncmp.c
@@ -178,5 +178,19 @@ main (int argc, char *argv[])
       }
   }
 
+  int volatile value;
+
+  /* Test zero-length operations on NULL pointers, allowed by
+     <https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3322.pdf>.  */
+
+  value = (wcsncmp (NULL, L"x", 0) == 0);
+  ASSERT (value);
+
+  value = (wcsncmp (L"x", NULL, 0) == 0);
+  ASSERT (value);
+
+  value = (wcsncmp (NULL, NULL, 0) == 0);
+  ASSERT (value);
+
   return test_exit_status;
 }
-- 
2.34.1