diff --git a/include/libxml/xmlschemas.h b/include/libxml/xmlschemas.h
index adaff3e37..e71dc9a14 100644
--- a/include/libxml/xmlschemas.h
+++ b/include/libxml/xmlschemas.h
@@ -217,7 +217,7 @@ XMLPUBFUN int
 	    xmlSchemaValidateStream	(xmlSchemaValidCtxtPtr ctxt,
 					 xmlParserInputBufferPtr input,
 					 xmlCharEncoding enc,
-					 xmlSAXHandlerPtr sax,
+					 const xmlSAXHandler *sax,
 					 void *user_data);
 XMLPUBFUN int
 	    xmlSchemaValidateFile	(xmlSchemaValidCtxtPtr ctxt,
diff --git a/xmlschemas.c b/xmlschemas.c
index d006d48be..256fef0d2 100644
--- a/xmlschemas.c
+++ b/xmlschemas.c
@@ -28789,7 +28789,7 @@ done:
 int
 xmlSchemaValidateStream(xmlSchemaValidCtxtPtr ctxt,
                         xmlParserInputBufferPtr input, xmlCharEncoding enc,
-                        xmlSAXHandlerPtr sax, void *user_data)
+                        const xmlSAXHandler *sax, void *user_data)
 {
     xmlParserCtxtPtr pctxt = NULL;
     xmlParserInputPtr inputStream = NULL;