HHVM 4.11 is released! This release marks the end of support for the 4.5.x series.


  • improved error locations for inst_meth()/class_meth() with private or protected methods.
  • added an admin server endpoint to remove units from the unit cache; for example: curl 'http://localhost:8003/invalidate-units?path=/my/file.php&path=/my/other/file.php'
  • type mismatch errors (4110) now report the full types
  • PHP sort functions are now annotated as inout instead of by-reference in the HHIs; both inout and references continue to work at runtime.
  • added hh_client --extract-standalone, to create self-contained files containing a function and all recursive dependencies.
  • bytecode is no longer regenerated for source files that are touched but have an unchanged SHA.
  • if, at runtime, a class uses multiple traits that declare the same method, the error message now includes the trait names.

Breaking Changes

  • the key generic for the darray type and the HH\darray() function (autoimported) is now required to be an arraykey.
  • PHP7-style anonymous function use() clause positioning is now a parser error; Hack requires use() after the return type, while PHP7 has use() before the return type.
  • dict(), vec(), and keyset() are now in the HH\ namespace; they remain autoimported, so this change only breaks fully-qualified references.