Composer Fails to Install Drush

Last modified: 
Thursday, October 1st, 2015

APC Enabled Server

If your server is running APC, that may interfere with Composer. You'll likely see errors like this

PHP Fatal error: include(): Cannot redeclare class symfony\component\process\process in phar:///usr/local/bin/composer/vendor/composer/ClassLoader.php on line 412

You can around this problem by calling composer by way of the php cli with the argument apc.enable_cli=0.

php -d "apc.enable_cli=0" /usr/local/bin/composer global require drush/drush:7.*

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