HHVM 4.121 is released! This release marks the end of support for 4.115; HHVM 4.116–4.120 remain supported, as do the 4.80 and 4.102 LTS releases.


  • When converting bools/resources/objects to ints, only raise a conversion notice or error, not both.
  • Added a new hhvm.notice_on_coerce_for_str_concat2 option to catch a coercion case that is not handled by hhvm.notice_on_coerce_for_str_concat. For both of these, a value of 0 means silent coercion, 1 raises a notice, and 2 is an error.

Breaking Changes

  • Errors are now raised by default when math operations have to implicitly coerce the type of an operand. This includes increment and decrement operators. In prior versions, this behavior can be controlled with the hhvm.notice_on_coerce_for_math and hhvm.notice_on_coerce_for_inc_dec INI settings.
  • A notice is now raised when comparison operators coerce types. This can be controlled with the hhvm.notice_on_coerce_for_cmp and hhvm.notice_on_coerce_for_eq INI settings.
  • Bitwise operations now raise an error when coercing types. On previous releases, this can be controlled with the hhvm.notice_on_coerce_for_bit_op INI setting.

See 4.120’s announcement for Legacy_FIXME functions to aid in type coercion migration.

Future Changes

  • The various coercion options will be removed over time, and implicit coercions will always be errors.