1 files changed, 3 insertions, 2 deletions
diff --git a/tree.c b/tree.c
index ffbcabd..432007e 100644
--- a/tree.c
+++ b/tree.c
@@ -4848,7 +4848,7 @@ xmlNodeSetBase(xmlNodePtr cur, const xmlChar* uri) {
     fixed = xmlPathToURI(uri);
     if (fixed != NULL) {
 	xmlSetNsProp(cur, ns, BAD_CAST "base", fixed);
-	xmlFree(fixed);
+	xmlFree((xmlChar *)fixed);
     } else {
 	xmlSetNsProp(cur, ns, BAD_CAST "base", uri);
     }
@@ -6968,7 +6968,8 @@ xmlBufferAdd(xmlBufferPtr buf, const xmlChar *str, int len) {
     if (len < 0)
         len = xmlStrlen(str);
 
-    if (len <= 0) return -1;
+    if (len < 0) return -1;
+    if (len == 0) return 0;
 
     needSize = buf->use + len + 2;
     if (needSize > buf->size){