diff --git a/tests/include/alt-dummy/threading_alt.h b/tests/include/alt-dummy/threading_alt.h
new file mode 100644
index 0000000000..ff2fed5e2a
--- /dev/null
+++ b/tests/include/alt-dummy/threading_alt.h
@@ -0,0 +1,27 @@
+/* threading_alt.h with dummy types for MBEDTLS_THREADING_ALT */
+/*
+ *  Copyright The Mbed TLS Contributors
+ *  SPDX-License-Identifier: Apache-2.0
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"); you may
+ *  not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+#ifndef THREADING_ALT_H
+#define THREADING_ALT_H
+
+typedef struct mbedtls_threading_mutex_t
+{
+    int dummy;
+} mbedtls_threading_mutex_t;
+
+#endif /* threading_alt.h */