Bug #69363 [Nab]: eval()ed string literal is not interned on PHP7+OPcache

Edit report at https://bugs.php.net/bug.php?id=69363&edit=1 ID: 69363 User updated by: for-bugs at hnw dot jp Reported by: for-bugs at hnw dot jp -Summary: eval()ed string literal is not intened on PHP7+OPcache +Summary: eval()ed string literal is not interned on PHP7+OPcache Status: Not a bug Type: Bug Package: opcache Operating System: any PHP Version: master-Git-2015-04-03 (Git) Block user comment: N Private report: N New Comment: Hmm. If you are right, enabling OPcache on PHP 7 causes little bit performance loss and consuming more memories when we use eval(). $ php7 -d 'opcache.enable_cli=Off' /tmp/test-script.php string(3) "baz" refcount(1) string(3) "baz" refcount(1) $ php7 -d 'opcache.enable_cli=On' /tmp/test-script.php string(3) "baz" refcount(1) string(3) "baz" refcount(2) Previous Comments: ------------------------------------------------------------------------ [2015-04-03 02:39:56] laruence@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 first of all, use or not use interned string, should not be cared about user land, it's a internal optimization, and also affects by intend string memory pool size . and for opcache, opcache won't do any optimization for EVAL_CODES. so...this behavior is expected. thanks ------------------------------------------------------------------------ [2015-04-03 00:58:37] for-bugs at hnw dot jp Description: ------------ On PHP7 without OPcache, eval('$bar="baz"') makes interned string. However, eval()ed string literal is dynamically allocated with OPcache enabled. The interned string on PHP7 is not refcounted. So, string refcount(2) means non-interned. Test script: --------------- <?php $foo="baz"; $eval_str='$bar="baz";'; eval($eval_str); debug_zval_dump($foo); debug_zval_dump($bar); Expected result: ---------------- string(3) "baz" refcount(1) string(3) "baz" refcount(1) Actual result: -------------- string(3) "baz" refcount(1) string(3) "baz" refcount(2) ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=69363&edit=1