fix mem leak in sxe_property_read

fix compiler warning

ext/simplexml/simplexml.c

@@ -26,6 +26,7 @@
 #include "php_ini.h"
 #include "ext/standard/info.h"
 #include "php_simplexml.h"
+#include "zend_execute_locks.h"
 
 zend_class_entry *sxe_class_entry;
 
@@ -105,8 +106,7 @@ sxe_property_read(zval *object, zval *member TSRMLS_DC)
 	xmlAttrPtr      attr;
 	int             counter = 0;
 
-	ALLOC_ZVAL(return_value);
-	return_value->refcount = 0;
+	MAKE_STD_ZVAL(return_value);
 	ZVAL_NULL(return_value);
 
 	name = Z_STRVAL_P(member);
@@ -146,7 +146,6 @@ sxe_property_read(zval *object, zval *member TSRMLS_DC)
 			if (match_ns(sxe, node, name)) {
 				MAKE_STD_ZVAL(value);
 				_node_as_zval(sxe, node->parent, value TSRMLS_CC);
-				value->refcount = 0;
 				APPEND_CUR_ELEMENT(counter, value);
 				goto next_iter;
 			}
@@ -156,8 +155,6 @@ sxe_property_read(zval *object, zval *member TSRMLS_DC)
 			APPEND_PREV_ELEMENT(counter, value);
 			MAKE_STD_ZVAL(value);
 			_node_as_zval(sxe, node, value TSRMLS_CC);
-			value->refcount = 0;
-
 			APPEND_CUR_ELEMENT(counter, value);
 		}
 
@@ -173,6 +170,9 @@ next_iter:
 		return_value = value;
 	}
 
+	/* create temporary variable */
+	PZVAL_UNLOCK(return_value);
+
 	return return_value;
 }
 /* }}} */
@@ -207,7 +207,7 @@ sxe_property_write(zval *object, zval *member, zval *value TSRMLS_DC)
 	php_sxe_object *sxe;
 	char           *name;
 	xmlNodePtr      node;
-	xmlNodePtr      newnode;
+	xmlNodePtr      newnode = NULL;
 	xmlAttrPtr      attr;
 	int             counter = 0;
 	int             is_attr = 0;