bug #17275 [PhpUnitBridge] Re-enable the garbage collector (nicolas-grekas)

This PR was merged into the 2.7 branch.

Discussion
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[PhpUnitBridge] Re-enable the garbage collector

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #17268, #11566
| License       | MIT
| Doc PR        | -

The bug is fixed in PHP and disabling the gc causes issues elsewhere.

Commits
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478710f [PhpUnitBridge] Re-enable the garbage collector

src/Symfony/Bridge/PhpUnit/README.md

@@ -5,7 +5,6 @@ Provides utilities for PHPUnit, especially user deprecation notices management.
 
 It comes with the following features:
 
- * disable the garbage collector;
  * enforce a consistent `C` locale;
  * auto-register `class_exists` to load Doctrine annotations;
  * print a user deprecation notices summary at the end of the test suite.

src/Symfony/Bridge/PhpUnit/bootstrap.php

@@ -17,12 +17,6 @@ if (!defined('PHPUNIT_COMPOSER_INSTALL') && !class_exists('PHPUnit_TextUI_Comman
     return;
 }
 
-if (PHP_VERSION_ID >= 50400 && gc_enabled()) {
-    // Disabling Zend Garbage Collection to prevent segfaults with PHP5.4+
-    // https://bugs.php.net/bug.php?id=53976
-    gc_disable();
-}
-
 // Enforce a consistent locale
 setlocale(LC_ALL, 'C');