Minecraftforge: [1.10.2] ConcurrentModificationException on server - no other mods installed

[Kuboczoch]

This is my crash report: http://hastebin.com/ozonibinak.pl
This can be easily triggered by issuing save-off, save-all via rcon

[marcin212]

Same problem without rcon
http://hastebin.com/ezalopoyeq.scala

[Aaron1011]

@Kuboczoch: This is a fundamental issue with RCon, not a Forge bug - it executes all of commands on another thread. A better solution is to simply avoid using RCon - it's completely unencrypted, so the password it uses is visible to anyone watching the network.

@marcin212: That appears to be a completely different issue, as you're using 71 mods.

[Kuboczoch]

I use RCon on localhost... @Aaron1011

[Pokechu22]

It's a vanilla issue, see MC-72390. Forge isn't really in the position to fix it (it could, but really it should be fixed on mojang's end).

[Heufneutje]

Forge fixes a few vanilla bugs. Usually they are submitted with the Mojang bug tracker number in a comment in the patch so it can easily be removed once Mojang fixes it.

[JustGregory-zz]

That really begs the question, does Mojang care what Forge "fixes" or not? If so, why wouldn't they adopt Forge's fixes even more quickly?

[Pokechu22]

Mojang does apply fixes from the community if they're on their bug tracker (at least, occasionally; for bigger fixes or "hacky" fixes they tend to use it as advice rather than a direct patch). I've contributed several bug fixes that way.

There is one other thing to consider (and I'm not completely in the know about it): Forge is LGPL, which makes it legally complicated for Mojang to use Forge patches. Just something to consider...

[stale[bot]]

This issue has been automatically marked as stale because it has not had activity in a long time, and will be closed if no further activity occurs. If this issue was overlooked, forgotten, or should remain open for any other reason, please reply here to call attention to it and remove the stale status. Thank you for your contributions.

[Pokechu22]

The issue is still present and the MC ticket has been updated.

[mezz]

I'm not sure if it is useful to keep Forge issues open for vanilla bugs unless there is active discussion.
I think it is probably good to keep discussion centralized on the Mojang tracker unless a PR is open for Forge. What do you think?

[Pokechu22]

Yeah, it'd be fine to close this and just keep the discussion on the tracker, just wanted to make it clear that the issue is still present.

[mezz]

Thanks! I will close this now.
For anyone reading, you should still feel free to open PRs to fix vanilla bugs if the fix is not too large.