diff --git a/lm-c99/tests/test_ig_c99/ig-c99/idl_core.h.target b/lm-c99/tests/test_ig_c99/ig-c99/idl_core.h.target
new file mode 100644
index 0000000..81a905c
--- /dev/null
+++ b/lm-c99/tests/test_ig_c99/ig-c99/idl_core.h.target
@@ -0,0 +1,18 @@
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// idl basetypes
+// -------------
+typedef char* string;
+typedef char* binary;
+typedef unsigned int uint;
+typedef size_t size;
+typedef void* opaque;
+
+
+#ifdef __cplusplus
+} // extern "C"
+#endif