Index: libxml2-2.13.8/schematron.c
===================================================================
--- libxml2-2.13.8.orig/schematron.c
+++ libxml2-2.13.8/schematron.c
@@ -1509,6 +1509,8 @@ xmlSchematronFormatReport(xmlSchematronV
             select = xmlGetNoNsProp(child, BAD_CAST "select");
             comp = xmlXPathCtxtCompile(ctxt->xctxt, select);
             eval = xmlXPathCompiledEval(comp, ctxt->xctxt);
+            if (eval == NULL)
+                return ret;
 
             switch (eval->type) {
             case XPATH_NODESET: {