Roll libxml to bdec2183f34b37ee89ae1d330c6ad2bb4d76605f

third_party/libxml/src/relaxng.c

Index: third_party/libxml/src/relaxng.c
diff --git a/third_party/libxml/src/relaxng.c b/third_party/libxml/src/relaxng.c
index 5779e7fc5f49e2b99c60f7ceb141ef1b79536825..56a3344a2fe1a198d23a11fdf6678b58b6719d85 100644
--- a/third_party/libxml/src/relaxng.c
+++ b/third_party/libxml/src/relaxng.c
@@ -507,7 +507,7 @@ xmlRngVErrMemory(xmlRelaxNGValidCtxtPtr ctxt, const char *extra)
  *
  * Handle a Relax NG Parsing error
  */
-static void
+static void LIBXML_ATTR_FORMAT(4,0)
 xmlRngPErr(xmlRelaxNGParserCtxtPtr ctxt, xmlNodePtr node, int error,
            const char *msg, const xmlChar * str1, const xmlChar * str2)
 {
@@ -541,7 +541,7 @@ xmlRngPErr(xmlRelaxNGParserCtxtPtr ctxt, xmlNodePtr node, int error,
  *
  * Handle a Relax NG Validation error
  */
-static void
+static void LIBXML_ATTR_FORMAT(4,0)
 xmlRngVErr(xmlRelaxNGValidCtxtPtr ctxt, xmlNodePtr node, int error,
            const char *msg, const xmlChar * str1, const xmlChar * str2)
 {
@@ -2215,7 +2215,8 @@ xmlRelaxNGGetErrorString(xmlRelaxNGValidErr err, const xmlChar * arg1,
         snprintf(msg, 1000, "Unknown error code %d\n", err);
     }
     msg[1000 - 1] = 0;
-    return (xmlStrdup((xmlChar *) msg));
+    xmlChar *result = xmlCharStrdup(msg);
+    return (xmlEscapeFormatString(&result));
 }
 
 /**