Created attachment 585770 [details, diff] lighttpd-1.4.54-fix-webdav-crash patch www-servers/lighttpd-1.4.54 immediately segfaults at startup when mod_webdav is active. Patch from upstream https://redmine.lighttpd.net/issues/2958 confirmed to fix this. Please add to ebuild.
I have also hit this, and it took me quite some time to figure out what is going on. The patch solves the problem. It makes much sense to add this patch to the tree, and it is not so much work.
Fairly forgot of this bug, but must be fixed as part of x.55 release in anyway.