Ошибка при установке XHP с композитором

Я пытаюсь установить XHP на OSX, используя композитор. У меня есть каталог с composer.phar и composer.json. Мой файл composer.json выглядит следующим образом:

{ "require": { "facebook/xhp-lib": "~2.2" } } 

Я также установил последнюю версию HHVM. Я попытался запустить

 hhvm composer.phar install --verbose 

но получил следующую ошибку:

 [ErrorException] Undefined index: 0 Exception trace: () at phar://composer.phar/bin/../src/../vendor/symfony/process/Pipes/AbstractPipes.php:140 Composer\Util\ErrorHandler::handle() at phar://composer.phar/bin/../src/../vendor/symfony/process/Pipes/AbstractPipes.php:140 Symfony\Component\Process\Pipes\AbstractPipes->write() at phar://composer.phar/bin/../src/../vendor/symfony/process/Pipes/UnixPipes.php:98 Symfony\Component\Process\Pipes\UnixPipes->readAndWrite() at phar://composer.phar/bin/../src/../vendor/symfony/process/Process.php:1359 Symfony\Component\Process\Process->readPipes() at phar://composer.phar/bin/../src/../vendor/symfony/process/Process.php:1279 Symfony\Component\Process\Process->updateStatus() at phar://composer.phar/bin/../src/../vendor/symfony/process/Process.php:305 Symfony\Component\Process\Process->start() at phar://composer.phar/bin/../src/../vendor/symfony/process/Process.php:201 Symfony\Component\Process\Process->run() at phar://composer.phar/bin/../src/../src/Composer/Util/ProcessExecutor.php:68 Composer\Util\ProcessExecutor->execute() at phar://composer.phar/bin/../src/../src/Composer/Package/Version/VersionGuesser.php:88 Composer\Package\Version\VersionGuesser->guessGitVersion() at phar://composer.phar/bin/../src/../src/Composer/Package/Version/VersionGuesser.php:67 Composer\Package\Version\VersionGuesser->guessVersion() at phar://composer.phar/bin/../src/../src/Composer/Package/Loader/RootPackageLoader.php:76 Composer\Package\Loader\RootPackageLoader->load() at phar://composer.phar/bin/../src/../src/Composer/Factory.php:332 Composer\Factory->createComposer() at phar://composer.phar/bin/../src/../src/Composer/Factory.php:552 Composer\Factory::create() at phar://composer.phar/bin/../src/../src/Composer/Console/Application.php:308 Composer\Console\Application->getComposer() at phar://composer.phar/bin/../src/../src/Composer/Console/Application.php:420 Composer\Console\Application->getPluginCommands() at phar://composer.phar/bin/../src/../src/Composer/Console/Application.php:131 Composer\Console\Application->doRun() at phar://composer.phar/bin/../src/../vendor/symfony/console/Application.php:123 Symfony\Component\Console\Application->run() at phar://composer.phar/bin/../src/../src/Composer/Console/Application.php:102 Composer\Console\Application->run() at phar://composer.phar/bin/composer:43 include() at /Users/chrisapa/Sites/project1/composer.phar:24 

Я не уверен, что делать дальше.