From D10078 Diff 1:
(PHL1) Unknown Symbol at line 54 Use of unknown class 'ZipArchive'. Common causes are: - Your libphutil/ is out of date. This is the most common cause. Update this copy of libphutil: /Users/btrahan/Dropbox/code/libphutil - Some other library is out of date. Update the library this symbol appears in. - This symbol is misspelled. Spell the symbol name correctly. Symbol name spelling is case-sensitive. - This symbol was added recently. Run `arc liberate` on the library it was added to. - This symbol is external. Use `@phutil-external-symbol`. Use `grep` to find usage examples of this directive. *** ALTHOUGH USUALLY EASY TO FIX, THIS IS A SERIOUS ERROR. *** THIS ERROR IS YOUR FAULT. YOU MUST RESOLVE IT.
This class isn't mentioned in php_compat_info.json.