diff --git a/gentest.py b/gentest.py
index 17c9f59..f178620 100755
--- a/gentest.py
+++ b/gentest.py
@@ -260,6 +260,7 @@
    "xmlParseChunk": "if (ctxt != NULL) {xmlFreeDoc(ctxt->myDoc); ctxt->myDoc = NULL;}",
    "xmlParseExtParsedEnt": "if (ctxt != NULL) {xmlFreeDoc(ctxt->myDoc); ctxt->myDoc = NULL;}",
    "xmlDOMWrapAdoptNode": "if ((node != NULL) && (node->parent == NULL)) {xmlUnlinkNode(node);xmlFreeNode(node);node = NULL;}",
+   "xmlBufferSetAllocationScheme": "if ((buf != NULL) && (scheme == XML_BUFFER_ALLOC_IMMUTABLE) && (buf->content != NULL) && (buf->content != static_buf_content)) { xmlFree(buf->content); buf->content = NULL;}"
 }
 
 modules = []