Bug #68765 [ReO->Csd]: Optimisation of constant definitions can cause incorrect output.

Edit report at https://bugs.php.net/bug.php?id=68765&edit=1 ID: 68765 Updated by: nikic@php.net Reported by: axel dot ml at warenform dot net Summary: Optimisation of constant definitions can cause incorrect output. -Status: Re-Opened +Status: Closed Type: Bug Package: opcache Operating System: Linux x86_64 PHP Version: 5.6.4 -Assigned To: +Assigned To: nikic Block user comment: N Private report: N New Comment: This has been fixed at some point with the addition of the ZEND_OPTIMIZER_PASS_15 ("collect constants") flag, which is disabled by default. Previous Comments: ------------------------------------------------------------------------ [2015-03-13 11:49:36] v dot leborgne at shop-application dot com I've done some more tests : PHP 5.6.6 and opcache disabled : "hello world" PHP 5.6.6 and opcache enabled: "hi world" PHP 5.5.22 and opcache disabled : "hello world" PHP 5.5.22 and opcache enabled : "hello world" ------------------------------------------------------------------------ [2015-03-13 11:39:22] v dot leborgne at shop-application dot com I experience the same issue with php 5.6.6 : myscript.php : define('FOO','hello'); include('somefile.php'); echo ANOTHER_FOO; somefile.php : define('FOO','hi'); define('ANOTHER_FOO',FOO.' world'); myscript.php prints : in PHP<5.6 : "hello world" in PHP5.6 : "hi world" ------------------------------------------------------------------------ [2015-01-07 19:23:54] leigh@php.net Apologies I didn't read properly. It seems to me this is unrelated to the @ operator at all then (yes the current bug title is misleading - I'll try and think of something more appropriate), as you state yourself, if you omit all of the @ operators the problem persists. I suspect there is some kind of optimisation being performed, and OpCache noticing that the include file has not changed, simply spits out the optimised output even though the execution conditions have changed. ------------------------------------------------------------------------ [2015-01-07 18:52:34] axel dot ml at warenform dot net I admit using an "@" here is misleading. But if you omit all "@"s the problem is still the same: The code behaves different, when turning opcache on. The seems to be a bug for me. ------------------------------------------------------------------------ [2015-01-07 15:58:08] leigh@php.net Thank you for taking the time to write to us, but this is not a bug. Please double-check the documentation available at http://www.php.net/manual/ and the instructions on how to report a bug at http://bugs.php.net/how-to-report.php The @ operator is not a conditional construct. It prevents any error from being displayed, it does not prevent the statement from executing. Checking the constant with if (!defined(...)) is the correct way to handle this situation. ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at https://bugs.php.net/bug.php?id=68765 -- Edit this bug report at https://bugs.php.net/bug.php?id=68765&edit=1