Bug #74164 [NEW]: PHP hangs when an invalid value is dynamically passed to typehinted by-ref arg.

From: shiranai7 at hotmail dot com Operating system: Windows, Linux PHP version: 7.1.2 Package: Scripting Engine problem Bug Type: Bug Bug description:PHP hangs when an invalid value is dynamically passed to typehinted by-ref arg. Description: ------------ Dynamically passing an invalid value to a typehinted function argument which is also passed by reference while a custom exception-throwing error handler is active will cause PHP to hang. Interesting observations: - doesn't happen in PHP versions prior to 7.1.0 - removing the namespace prevents the bug from happening - the error handler must throw an exception for the hang to occur - the call must be dynamic or a fatal error is produced instead - the kind of typehint doesn't seem to matter (it happens with array, a class, a scalar typehint etc.) Test script: --------------- <?php namespace Foo; set_error_handler(function () { throw new \Exception(); }); call_user_func(function (array &$ref) {}, 'not_an_array_variable'); Expected result: ---------------- Fatal error: Uncaught Exception in script.php on line 6 Exception: in script.php on line 6 Call Stack: 0.0010 412712 1. {main}() script.php:0 0.0010 413352 2. call_user_func:{script.php:9}() script.php:9 0.0010 416144 3. Foo\{closure}() script.php:9 Actual result: -------------- The script doesn't terminate. PHP hangs indefinitely. -- Edit bug report at https://bugs.php.net/bug.php?id=74164&edit=1 -- Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=74164&r=trysnapshot54 Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=74164&r=trysnapshot55 Try a snapshot (trunk): https://bugs.php.net/fix.php?id=74164&r=trysnapshottrunk Fixed in SVN: https://bugs.php.net/fix.php?id=74164&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=74164&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=74164&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=74164&r=needscript Try newer version: https://bugs.php.net/fix.php?id=74164&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=74164&r=support Expected behavior: https://bugs.php.net/fix.php?id=74164&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=74164&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=74164&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=74164&r=globals PHP 4 support discontinued: https://bugs.php.net/fix.php?id=74164&r=php4 Daylight Savings: https://bugs.php.net/fix.php?id=74164&r=dst IIS Stability: https://bugs.php.net/fix.php?id=74164&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=74164&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=74164&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=74164&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=74164&r=mysqlcfg