More changes for HPHP to help make it clang friendly ~~~hphp/compiler/expression/constant_expression.h ~~~hphp/compiler/expression/function_call.h rfind returns a size_t/unsigned int ~~~hphp/runtime/base/server/http_protocol.cpp Switched to std::to_string. Assuming [] was not intended here ~~~hphp/runtime/base/ref_data.h These fields were accessed in a public manner, assuming public was intended instead of private ~~~hphp/runtime/base/variable_serializer.cpp Switched to using [] and & to make clang happy. Assuming this was to either take or drop the first char. ~~~hphp/runtime/ext/asio/asio_external_thread_event_queue.h ~~~hphp/runtime/ext/asio/asio_external_thread_event_queue.cpp Cast which performs the conversions of a reinterpret_cast is not allowed in a constant expression. This is been moved to a macro as a temporary fix. +++hphp/runtime/ext/ext_misc.cpp Added std::atomic to supress warnings ~~~hphp/runtime/vm/jit/simplifier.cpp Chosen constructor is explicit in copy-initialization ~~~hphp/runtime/vm/jit/translator-asm-helpers.S Ambiguous instructions require an explicit suffix Changed cmp to cmpl ~~~hphp/runtime/vm/jit/translator-x64-helpers.cpp Clang does not support global register variables +++hphp/runtime/vm/unwind.cpp describeFault was only used when DEBUG or USE_TRACE was defined ~~~hphp/runtime/vm/verifier/check_unit.cpp Made fmt pointer const to avoid string format issues/warnings ~~~hphp/util/stack_trace.cpp Clang does not support variable-length arrays. Uniqe_ptr is used instead to take advantage runtime-sized arrays, a restriced form of variable-length arrays ~~~hphp/util/thread_local.h Clang seems to be supporting the __thread attribute, or at the very least it is not complaining about it. ~~~hphp/util/tiny_vector.h Clang does not like the flexible array here, since T is not always POD. I have reimplemented the array here by just sticking one value in the struct and calculating the offset from its address manually. Alterinatively, we could change the the non-POD types to be pointers, or we could edit their implemenations. +++hphp/util/util.h Created a template for the union, A function declared with the constexpr specifier cannot contain type declarations that do not define classes or enumerations +++hphp/runtime/vm/jit/x64-util.h Added a TODO The way hphp/runtime/vm/jit/x64-util.h is currently implemented, it only works if USE_GCC_FAST_TLS is defined
HipHop VM for PHP 
HipHop VM (HHVM) is a new open-source virtual machine designed for executing programs written in PHP. HHVM uses a just-in-time compilation approach to achieve superior performance while maintaining the flexibility that PHP developers are accustomed to. HipHop VM (and before it HPHPc) has realized > 5x increase in throughput for Facebook compared with Zend PHP 5.2.
HipHop is most commonly run as a standalone server, replacing both Apache and modphp.
Installing
You can install a prebuilt package or compile from source.
Running
You can run standalone programs just by passing them to hhvm: hhvm my_script.php.
HipHop bundles in a webserver. So if you want to run on port 80 in the current directory:
sudo hhvm -m server
For anything more complicated, you'll want to make a config.hdf and run sudo hhvm -m server -c config.hdf.
Contributing
We'd love to have your help in making HipHop better. If you run into problems, please open an issue, or better yet, fork us and send a pull request. Join us on #hhvm on freenode.
If you want to help but don't know where to start, try fixing some of the Zend tests that don't pass. You can run them with hphp/test/run. When they work, move them to zend/good and send a pull request.
Before changes can be accepted a Contributors Licensing Agreement (pdf - print, sign, scan, link) must be signed.
Licence
HipHop VM is licensed under the PHP and Zend licenses except as otherwise noted.