diff --git a/tests/baz/1.0/Android.mk b/tests/baz/1.0/Android.mk
index 165237f..a0b36b0 100644
--- a/tests/baz/1.0/Android.mk
+++ b/tests/baz/1.0/Android.mk
@@ -9,6 +9,23 @@
 HIDL := $(HOST_OUT_EXECUTABLES)/hidl-gen$(HOST_EXECUTABLE_SUFFIX)
 
 #
+# Build types.hal
+#
+GEN := $(intermediates)/android/hardware/tests/baz/1.0/types.cpp
+$(GEN): $(HIDL)
+$(GEN): PRIVATE_HIDL := $(HIDL)
+$(GEN): PRIVATE_DEPS := $(LOCAL_PATH)/types.hal
+$(GEN): PRIVATE_OUTPUT_DIR := $(intermediates)
+$(GEN): PRIVATE_CUSTOM_TOOL = \
+    $(PRIVATE_HIDL) -o $(PRIVATE_OUTPUT_DIR) \
+    -Lc++ -randroid.hardware:hardware/interfaces \
+    android.hardware.tests.baz@1.0::types
+
+$(GEN): $(LOCAL_PATH)/types.hal
+	$(transform-generated-source)
+LOCAL_GENERATED_SOURCES += $(GEN)
+
+#
 # Build IBase.hal
 #
 GEN := $(intermediates)/android/hardware/tests/baz/1.0/BaseAll.cpp
diff --git a/tests/baz/1.0/types.hal b/tests/baz/1.0/types.hal
new file mode 100644
index 0000000..030dbe5
--- /dev/null
+++ b/tests/baz/1.0/types.hal
@@ -0,0 +1,23 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * 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.
+ */
+
+package android.hardware.tests.baz@1.0;
+
+/*
+ * Verify that introducing a typedef in types.hal does not mistakenly emit
+ * a makefile section to create a dedicated ulong.java class as it used to.
+ */
+typedef uint32_t ulong;