Pasting Causes Crash

[Extrementhusiast]

Occasionally, when I try to paste something from a different algorithm, Golly crashes. Any idea why? (Windows XP, paste was set to "only change rule if empty" at the time)

[Sphenocorona]

I've had this problem too sometimes and one time it made me lose a bunch of work I was really happy about, on Golly 2.3 (Win. Vista, I haven't updated it on this one because I don't have enough time to sort out all the stuff I want to keep) I think at least once it happened for me on Linux with 2.5 (I tried to paste and the program just instantly closed). For both the past rule changing was the same as for above.

[dvgrn]

I've had this problem too sometimes and one time it made me lose a bunch of work I was really happy about...

May this never happen again, then!

-- But if it does, could you keep a copy of whatever was in your clipboard buffer at the time, and post it to this thread? Also, if you can reconstruct it, mention what Golly's current rule was at the time of the crash... and attach your current GollyPrefs file.

I don't think I've ever seen a crash due to a paste-related algorithm change -- though I do have my own apparently unique difficulties, with the Undo system, and with the toolbars and menus turning into ineffective ghosts [not that the toolbars' appearance changes at all, just that when I click on them they don't register -- I end up "clicking through" into the universe behind them instead.]

[Andrew]

Occasionally, when I try to paste something from a different algorithm, Golly crashes.

I've never seen this on any of my systems (Mac OS 10.6, Windows XP, Linux Mint 13). But any bug that can cause loss of data is very serious, so I'll happily pay $50 to the 1st person who can come up with a sequence of steps that reproduces the bug on any of my systems. It doesn't have to be 100% reproducible -- even if it only occurs, say, 10% of the time, that should be enough to let me find and fix the bug.

[Extrementhusiast]

Take a large, organized pattern in LifeHistory, and run it for a few generations. Duplicate the layer. Set the rule to "012345678//3" and advance by one step to clear the history. Ctrl-C everything and switch back to the first layer. Attempt to paste into the layer using V. After the command, Golly 2.5 will sometimes crash. (I have it set to "change rule when universe is empty". I have not seen it crash yet if it is set to "never change rule".)

(I cannot remember the precise way to do this, as I am away from my usual computer at this time.)

[Sphenocorona]

I came up with another method that's rather simple:
1. This step is essentially the same as Extremeenthusiast's first step: Create a large, translationally symmetric pattern in a RuleLoader rule like extendedlife or LifeHistory. I chose Onion Rings agar and using tile-with-clip.py to speed things up.
2. Add a new layer.
3. Change the algorithm to something else. I chose JvN.
4. Create a bunch more new layers, like 5 or more (the more there are, the more trials you get.) None of these should be in the RuleLoader algorithm.
5. Ctrl-C the pattern you made in step 1, and start quickly pasting it into each of the blank layers in order.

If Golly does not crash, then you can undo back to the non-RuleLoader algorithm(s) on all the layers except the first and try again.

[Andrew]

Take a large, organized pattern in LifeHistory, and run it for a few generations. ...

Thanks for that info! I've managed to reproduce the crash on my Win and Linux systems (but never on my Mac for some reason). Those steps don't always crash, but often enough that it should let me find and fix the bug. When I do I'll make new beta versions of 2.6 for you to try. Send me some email (see Help > Known Problems for my address) and we'll discuss how best to send you the $50 reward!

[Extrementhusiast]

I'm actually thinking of reoffering as some sort of prize. It's probably going to do with finding the missing oscillator periods, but I haven't decided the specifics yet. (Another option is finding another cellular automaton that shows highly Life-like behavior, but is not Life.)

EDIT: The missing periods match up quite nicely. Find an oscillator of period 19, 23, 34, 38, or 41, and you'll earn yourself ten bucks per new period found.

[Andrew]

I've found and fixed the bug that causes Golly to crash when doing a paste. In the process of doing this I also fixed a couple of other bugs, one of which might be the cause of Dave's undo/redo problem, so please download and test these new builds:

http://www.trevorrow.com/golly/golly-2.6b2-win.zip (for Windows)
http://www.trevorrow.com/golly/golly-2.6b2-gtk.tar.gz (for Linux)

Both are 32-bit builds. If you need 64-bit builds let me know and I'll ask the other Golly devs to create them.

If after a few weeks of testing there are no problems then I'll do a full 2.6 release.