HHVM 3.8.1 发布，更新内容如下：
- Remove global LDAP requirement
- Don't require libXSLT globally
- Remove the global MCrypt requirement
- Remove the global search for LibUODBC
- Remove the global check for libpam
- use folly::writeFull wrapper for uploads
- Fix vararg handling for array_uintersect and others
- fix error message for abstract type constants
- Fix variadics in hhvm_get_frame_args
- Use poll() instead of select() in XDebugServer::createSocket.
- [hack] Error on overriding concrete type constant with an abstract one
- [hack] Grow shapes more correctly
- Array pointer modification functions (next, current, each etc) can be used on ArrayObject
- Eliminate ext_mbstring's dependence on ext_process
- Eliminate ext_mail's dependence on ext_process
- Use utf8 string literals in zend-html
- Don't allow abstract memoized methods
- [hack] Properly handle 'this' type for methods
- Fix lexing of "${fn()}"
- Fix lexing of #- [hack] Fix infinite loop in syntax error when closing a namespace
- Fix mispelling of COOKIE.
- Deal with self, static and parent constructors
下载：https://github.com/facebook/hhvm/archive/HHVM-3.8.1.zip。
HipHop VM(HHVM)是Facebook推出的用来执行PHP代码的虚拟机，它是一个PHP的JIT（Just-In- Time）编译器，同时具有产生快速代码和即时编译的优点。
Facebook表示，HHVM将替代HPHPi，用于所有的PHP执行。根据 Facebook透漏，HHVM在速度方面获得了显著改进，比目前使用的PHP解释器快60%，而使用内存减少90%。
Facebook于12年十二月初发布了一个博文，宣布他们的解释型PHP运行环境HHVM（HipHop VM）已经达到甚至超过了编译型PHP运行环境HipHop的运行速度。
来自:开源中国社区
