Fix destruction of suspended generators in suspended fibers during shutdown #15158
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bwoebi
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Zend/zend_generators.c
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| @@ -722,6 +774,13 @@ ZEND_API void zend_generator_resume(zend_generator *orig_generator) /* {{{ */ | |||
| return; | |||
| } | |||
|
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| if (EG(active_fiber)) { | |||
| orig_generator->flags |= ZEND_GENERATOR_IN_FIBER; | |||
| if (generator != orig_generator) { | |||
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Redundant condition (a few lines deeper as well).
…utdown The generator destructor is a no-op when the generator is running in a fiber, because unwinding the fiber will resume the generator. Normally the destructor is never called in this case, but this can happen during shutdown. We detect that a generator is running in a fiber with the ZEND_GENERATOR_IN_FIBER flag. This change fixes two cases in which this mechanism was broken: - The flag was not added when resuming a 'yield from $nonGenerator', as this is handled in a separate code path - When a generator that is running in a fiber has multiple children (aka multiple generators yielding from it), all of them could be considered to also run in a fiber (only one actually is), and could leak if not destroyed before shutdown.
bwoebi
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* PHP-8.2: [ci skip] NEWS Fix destruction of generator running in fibers during shutdown (#15158)
arnaud-lb
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* PHP-8.3: [ci skip] NEWS [ci skip] NEWS Fix destruction of generator running in fibers during shutdown (#15158)
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Fixes #15108.
In #10462 we ensured that generators running in a fiber are not destroyed before the fiber:
This was extended to support
yield fromin 00be6e1 and b9bca2d (I can not find the related PR anymore).Here I fix two additional cases not handled by #10462:
The
ZEND_GENERATOR_IN_FIBERflag was not added when resuming ayield from $nonGenerator. I fix that by adding the flag earlier.When a generator that is running in a fiber has multiple children (aka multiple generators yielding from it), all of them could be considered to also run in a fiber (only one actually is), and could leak if not destroyed before shutdown.
Unfortunately the second one requires traversing the child tree (at most once) during dtor if the root is marked
ZEND_GENERATOR_IN_FIBER.