EntityIter - RunTimeError: Access violation - no RTTI data!

[Frag1337]

Hello,

I'm sometimes getting this error while iterating through EntityIter(). (Mostly after map change)

[SP] Caught an Exception:
Traceback (most recent call last):
  File "..\addons\source-python\packages\source-python\events\listener.py", line 92, in fire_game_event
    callback(game_event)
  File "..\addons\source-python\plugins\test\libs\misc\triggers.py", line 58, in round_start
    hook_triggers()
  File "..\addons\source-python\plugins\test\libs\misc\triggers.py", line 81, in hook_triggers
    for trigger_multiple in EntityIter('trigger_multiple'):
  File "..\addons\source-python\packages\source-python\filters\iterator.py", line 56, in __iter__
    if self._is_valid(item):
  File "..\addons\source-python\packages\source-python\filters\entities.py", line 65, in _is_valid
    elif self.exact_match and check_name == entity.classname:

RuntimeError: Access violation - no RTTI data!

[jordanbriere]

Complete code?

[Frag1337]

I will update this once I figgure out, how to reproduce it.

[jordanbriere]

I will update this once I figgure out, how to reproduce it.

I asked for your code to confirm, but I'm pretty sure this happens because your plugin must request an entity instance after the internal cache was invalidated (through an OnEntityDeleted callback that is called after SP's) resulting into freed entities being iterated over later on. This is something that is fixed into #292, but that branch haven't been reviewed as of yet and thus haven't been merged. If you can get it compiled for your game/platform and confirm everything is working as it used to or reports any issues you may notice it would be appreciated. Thanks!

[Frag1337]

Thank you for the quick answer @jordanbriere!

The code was simply an iterate through EntityIter, and I didnt wanted to post my whole private plugin in here, thats why I was trying to reproduce it but didnt succeed.

I actually had this same problem in the morning again, but it happened after my plugin failed to load, but as I said, I dont know how to reproduce it exactly.

Sadly I dont know how to recompile it, else I would help you out.

[Frag1337]

That pull request looks also very interesting. Hope it gets pushed soon! Thanks for your work.

[jordanbriere]

I dont know how to reproduce it exactly.

It can be reproduced with the following code:

from entities.entity import Entity
from listeners import OnEntityDeleted
from listeners.tick import Delay

# Create an entity, which will be internally cached
entity = Entity.create('info_null')

# Store its index
index = entity.index

@OnEntityDeleted
def on_entity_deleted(base_entity):
    # This listener is being called after SP's, meaning that
    # requesting an instance of this entity will cache a new
    # instance after it was invalidated
    Entity(base_entity.index)

# Remove the entity, which will call the above callback
entity.remove()

def print_classname(index):
    print(Entity(index).classname)

# Attempt to print the classname after the deletion was processed
Delay(1, print_classname, (index,))


"""
[SP] Caught an Exception:
Traceback (most recent call last):
  File "..\addons\source-python\packages\source-python\listeners\tick.py", line 80, in _tick
    self.pop(0).execute()
  File "..\addons\source-python\packages\source-python\listeners\tick.py", line 161, in execute
    return self.callback(*self.args, **self.kwargs)
  File "..\addons\source-python\plugins\testing\testing.py", line 22, in print_classname
    print(Entity(index).classname)

RuntimeError: Access violation - no RTTI data!
"""

Which I assume is what happens for you; the entities are re-cached after the internal cache was invalidated, the indexes re-used by different entities on the new map and iterated over by EntityIter. On the other branch, that code is correctly throwing an exception rather than returning an instance that was re-cached after invalidation:

[SP] Caught an Exception:
Traceback (most recent call last):
  File "..\addons\source-python\packages\source-python\listeners\tick.py", line 80, in _tick
    self.pop(0).execute()
  File "..\addons\source-python\packages\source-python\listeners\tick.py", line 161, in execute
    return self.callback(*self.args, **self.kwargs)
  File "..\addons\source-python\plugins\testing\testing.py", line 22, in print_classname
    print(Entity(index).classname)
  File "..\addons\source-python\packages\source-python\entities\_base.py", line 131, in __call__
    obj = super().__call__(index)
  File "..\addons\source-python\packages\source-python\entities\_base.py", line 209, in __init__
    super().__init__(index)

ValueError: Conversion from "Index" (57) to "BaseEntity" failed.

[Frag1337]

Looks like I still run into this problem.

On some occasion I'm getting this:

[SP] Caught an Exception:
Traceback (most recent call last):
  File "..\addons\source-python\packages\source-python\plugins\command.py", line 164, in load_plugin
    plugin = self.manager.load(plugin_name)
  File "..\addons\source-python\packages\source-python\plugins\manager.py", line 194, in load
    plugin._load()
  File "..\addons\source-python\packages\source-python\plugins\instance.py", line 74, in _load
    self.module = import_module(self.import_name)
  File "..\addons\source-python\plugins\debug\debug.py", line 4, in <module>
    for trigger_multiple in EntityIter('trigger_multiple'):
  File "..\addons\source-python\packages\source-python\filters\iterator.py", line 56, in __iter__
    if self._is_valid(item):
  File "..\addons\source-python\packages\source-python\filters\entities.py", line 65, in _is_valid
    elif self.exact_match and check_name == entity.classname:

RuntimeError: Access violation - no RTTI data!

with following code:

from filters.entities import EntityIter


for trigger_multiple in EntityIter('trigger_multiple'):
    index = trigger_multiple.index
    target_name = trigger_multiple.target_name

Checksum      : a4fdf0d2adc411856c723f7d8aede00d
Date          : 2020-05-09 16:25:27.174220
OS            : Windows-10-10.0.18362
Game          : css
SP version    : None
Github commit : None

Notice I'm using your build from here: #292 (comment)

The only sourcemod plugin which could maybe interrupt would be this one here:

https://github.com/jason-e/rngfix/blob/bdd2f7fda5f4cbf9b3066c2e3db964bfcf503934/plugin/scripting/rngfix.sp#L283

[jordanbriere]

Before or after 1b67129? I've updated the builds yesterday after this commit, which was causing entities to only be cached if they carry the EFL_NO_DISSOLVE flag, regardless if they were marked for deletion or not. Make sure you use the core.dll from that build.

[Frag1337]

I used the version before that. Let me try.

[Frag1337]

@jordanbriere Looks like 1b67129 fixxed that. Nice!

I dont get that error message after map change anymore.