Detect and warn about APC 3.1.14 / 3.1.15

Summary:
These versions are broken, but package distros seem to be picking them up. :/

Since the error you get is completely useless, fatal immediately with a useful message.

Ref T2594.

Test Plan: Faked verisions and hit the issue.

Reviewers: btrahan

Reviewed By: btrahan

CC: brennantaylor, Arijit, aran

Maniphest Tasks: T2594

Differential Revision: https://secure.phabricator.com/D6415

src/applications/config/check/PhabricatorSetupCheckAPC.php

@@ -6,7 +6,8 @@ final class PhabricatorSetupCheckAPC extends PhabricatorSetupCheck {
     if (!extension_loaded('apc')) {
       $message = pht(
         "Installing the PHP extension 'APC' (Alternative PHP Cache) will ".
-        "dramatically improve performance.");
+        "dramatically improve performance. Note that APC versions 3.1.14 and ".
+        "3.1.15 are broken; 3.1.13 is recommended instead.");
 
       $this
         ->newIssue('extension.apc')

support/PhabricatorStartup.php

@@ -254,6 +254,21 @@ final class PhabricatorStartup {
         "disable it to run Phabricator. Consult the PHP manual for ".
         "instructions.");
     }
+
+    if (extension_loaded('apc')) {
+      $apc_version = phpversion('apc');
+      $known_bad = array(
+        '3.1.14' => true,
+        '3.1.15' => true,
+      );
+      if (isset($known_bad[$apc_version])) {
+        self::didFatal(
+          "You have APC {$apc_version} installed. This version of APC is ".
+          "known to be bad, and does not work with Phabricator (it will ".
+          "cause Phabricator to fatal unrecoverably with nonsense errors). ".
+          "Downgrade to version 3.1.13.");
+      }
+    }
   }