Introduced in httpd-1.3.3, the "VARIANTS" feature of mod_speling sets the VARIANTS environment variable to a list of alternative URL spellings. The purpose was to allow an ErrorDocument 300 handler to reformat the list. The feature was added in response to a specific user request -- see http://archive.apache.org/gnats/2859 But the feature was promptly broken in httpd-1.3.5, and has been broken in all releases since, so it can hopefully be assumed that no one uses it. The format of the VARIANTS list is supposed to be "url";"reason","url";"reason"... But when dgaudet made a change (SVN revision 82699) to fix O(n^2) memory consumption in mod_speling, suddenly the VARIANTS output would contain four extra commas per variant URL... It is now ",url,";",reason,",",url,";",reason,"... To fix the bug, you'd need to use apr_pstrcat to assemble the "url";"reason" string for each variant and then join all the assembled strings with commas. What happens now is that it places pieces of the strings in an array and then joins all the pieces with commas. But it's altogether likely that no one would care if it just went away. See bug #38923 for an overlapping pending change in mod_speling. I would also argue that in light of bug #38923, correct usage of VARIANTS would be fairly difficult for an end user even without the stray commas.
Please help us to refine our list of open and current defects; this is a mass update of old and inactive Bugzilla reports which reflect user error, already resolved defects, and still-existing defects in httpd. As repeatedly announced, the Apache HTTP Server Project has discontinued all development and patch review of the 2.2.x series of releases. The final release 2.2.34 was published in July 2017, and no further evaluation of bug reports or security risks will be considered or published for 2.2.x releases. All reports older than 2.4.x have been updated to status RESOLVED/LATER; no further action is expected unless the report still applies to a current version of httpd. If your report represented a question or confusion about how to use an httpd feature, an unexpected server behavior, problems building or installing httpd, or working with an external component (a third party module, browser etc.) we ask you to start by bringing your question to the User Support and Discussion mailing list, see [https://httpd.apache.org/lists.html#http-users] for details. Include a link to this Bugzilla report for completeness with your question. If your report was clearly a defect in httpd or a feature request, we ask that you retest using a modern httpd release (2.4.33 or later) released in the past year. If it can be reproduced, please reopen this bug and change the Version field above to the httpd version you have reconfirmed with. Your help in identifying defects or enhancements still applicable to the current httpd server software release is greatly appreciated.