I got excited to see a new patched version of libxml2-2.9.4 come down the pipe on Arch Linux (2.9.4+0+gbdec218-2 -> 2.9.4+4+g3169602-1), but alas ... it doesn't resolve this issue. It's just a couple of cherry-picked commits from the official libxml2 git repo made since 2.9.4's release.