Editing issue description – my memory was faulty, and this previously mentioend problem is not really an issue...
* DEFAULT_DEFAULT_CORE_NAME is not properly supported for the "old" style solr.xml if defaultCoreName="..." is not
specified in the solr.xml
That is not actually how defaultCoreName="..." has ever worked, i was remembering incorrectly – in the old style solr.xml, if you didn't have a defaultCoreName declared, you did not have a default core name (just like "adminPath")
I'm scaling back my patch to only use DEFAULT_DEFAULT_CORE_NAME in the case of hte "new style" config, similar to how adminPath is hardcoded to "/admin/cores". (same reasons as mentioned before: this gets the 4x and trunk example and simple single core cases working again with simple URLs)
Jan: as mentioned, my initial impressions about the impact of this bug were wrong, it really only affects the "new style" example on the 4x & trunk branchs, and doesn't seem to really affect anyone using existing "old style" solr.xml files.