Indexing an array with a persistent string triggers an assertion failure during destruction about php-src HOT 4 CLOSED

Yes, don't put non-interned persistent strings into non-persistent hashtables (array_init creates a non-persistent hashtable), it's not permitted.

Either intern the string (in minit) or allocate a non-persistent one.

from php-src.

it's not permitted.

Two questions:

1. Should this then be verified during insertion?
2. Why does this work for raw (non-array) HashTables then:

	HashTable array;
	zend_hash_init(&array, 0, NULL, ZVAL_PTR_DTOR, 0);

	zval value;
	ZVAL_LONG(&value, 1);

	zend_string *key = zend_string_init("foo", strlen("foo"), 1);
	zend_hash_update(&array, key, &value);
	zend_string_release(key);

	zend_hash_destroy(&array);

I also believe this is unnecessarily restrictive. Persistent strings should outlive the request-specific array, resulting in needless duplication when using them to index the array, no?

from php-src.

Okay, to be more precise: it's not permitted for arrays exposed as zvals to userland. The zend_array_destroy() API is used for pure runtime things.

You can do it for raw hashtables. But the goal of not permitting this is mostly so that you avoid accidentally exposing a refcounted persistent key to userland, which in threaded environments may lead to race conditions.
As long as you mutex these or keep the persistent string bound to a thread, it's fine.

from php-src.

Understood, thanks for the clarification.

from php-src.