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Fix lazy proxy calling magic methods twice #18039

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@arnaud-lb arnaud-lb commented Mar 13, 2025

Fixes GH-18038.

Guard the underlying property, so that the forwarded operation accesses the property directly.

@@ -970,6 +982,43 @@ static zend_always_inline bool property_uses_strict_types(void) {
&& ZEND_CALL_USES_STRICT_TYPES(EG(current_execute_data));
}

static zend_always_inline zval *forward_write_to_lazy_object(zend_object *zobj,
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I don't know if it's worth to always_inline this?

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Indeed, I will check if it makes a noticeable difference

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I've removed the always inline attribute

var_dump($obj->prop);

?>
--EXPECTF--
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I don't understand why the __get function should get called before instantiating the object? I.e. why does "C::__get" appear before "init"?

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It’s how lazy objects are supposed to behave: we interact primarily with the proxy (we execute the proxy’s code), but any access to its state is forwarded to the real instance.

So here we execute the getter, which tries to access a property. This triggers initialization before the access is forwarded.

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Okay I see, not what I intuitively expected but it makes sense

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I suppose there's also an implicit assumption here that the initialized properties does not contain dynamic properties. If it does, the initializer would need to be called before __get, to ensure that the property is actually still does not exist after the initializer has been called.

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I didn't find any other issues. If the aforementioned dynamic property behavior is correct, then this LGTM.

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3 participants