I'm reporting it here, because I have nothing installed (just clean ElkArte 1.0).
RSS is working fine for me, but from some time I see in error log this two entries:
URL: index.php?action=.xml;type=atom;limit=5
2: mysqli_free_result() expects parameter 1 to be mysqli_result, null given
File: /sources/database/Db-mysql.class.php
Line: 543
540: public function free_result($result)
541: {
542: // Just delegate to MySQL's function
==>543: mysqli_free_result($result);
544: }
URL: index.php?action=.xml;type=atom;limit=5
2: mysqli_num_rows() expects parameter 1 to be mysqli_result, null given
File: /sources/database/Db-mysql.class.php
Line: 554
551: public function num_rows($result)
552: {
553: // Simply delegate to the native function
==>554: return mysqli_num_rows($result);
555: }