warning on line 790 of wp-includes/rewrite.php

[Denis-de-Bernardy]

on sites with verbose rules and no static pages, the rewrite rule generator complains that it cannot array_reverse a non-array.

the culprit is get_page_hierarchy():

http://core.trac.wordpress.org/browser/trunk/wp-includes/post.php#L2401

it should return an empty array instead of null.

patches attached for trunk and 2.9 branch.

(In [12571]) Return empty array instead of null. Props Denis-de-Bernardy. fixes #11661 for trunk

(In [12572]) Return empty array instead of null. Props Denis-de-Bernardy. fixes #11661 for 2.9

Oops, looks like this is the same as #11578, which already had a trunk commit.

The other patch makes a more conservative patch higher up the stack. I'd normally prefer that, but inadvertent API changes suck and if you don't fix them quickly they build momentum.