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I ran into several other JIT bugs working on Google Maps. Since I worked on location, my code was the first complex thing that ran under most flows, and rather prone to being the first thing to crash when the system behaved in a very dumb way. About once a year we'd get a spike of crash reports from some ancient version of Android where a third party had built a custom JIT to get the system to run on very cheap hardware. Then the crash would be something absurd, like a null pointer on a value that was never assigned null, or an ArrayIndexOutOfBounds on a statically sized array that was only ever accessed with constants.

Sometimes someone would actually try to solve these, but I preferred the times where someone just changed the Proguard config and hope it shuffled things around enough that it didn't trigger whatever bug the JIT had.




> spike of crash reports from some ancient version of Android

Quasi-related question: app installs/updates have been very very consistently SIGBUSing system_server with BUS_ADRALN on my ancient Galaxy Note 3 for about a year, but downgrading the Play Store app to the factory version (5.5.12 :D) makes the problem go away completely.

I've tentatively considered writing something up for issuetracker.google.com, but besides tons of logcats I'm not sure what info to provide, and I also wonder if the info would be considered useful due to the age of the device. Any advice on whether/how to proceed would be appreciated!


I think the biggest problem you're going to run into is that there are very few people assigned to maintaining old systems, and it's quite hard to get these issues brought to anyone's attention. The ones I mentioned only got fixed because they crept up to the top most common causes of crashes.

A bug report would be the first thing I'd want for something like this - in addition to logcat info it includes a bunch of process information, and apps can add custom data to the report. It'd also be nice to know anything to narrow down when the problem started - whatever bounds you can provide on when you were last absolutely certain it was up to date and working, plus your best guess. Someone's going to have to dig a Galaxy Note 3 out of a drawer somewhere, go into the archives of old Play Store versions, and try installing them until they find the version that broke it, so anything that makes that binary search process less terrible would be a start.


Thanks for replying!

> there are very few people assigned to maintaining old systems, and it's quite hard to get these issues brought to anyone's attention. The ones I mentioned only got fixed because they crept up to the top most common causes of crashes.

Thanks for this info. It kinda matched my own intuition about what to expect, but I wasn't sure where/how I might find out for sure. It's nice to be able to calibrate how to optimize effort.

> A bug report would be the first thing I'd want for something like this - in addition to logcat info it includes a bunch of process information, and apps can add custom data to the report.

Ah, of course. That's straightforward to do; I can just watch logcat for system_server crashes then automatically take bug reports when they occur.

> It'd also be nice to know anything to narrow down when the problem started - whatever bounds you can provide on when you were last absolutely certain it was up to date and working, plus your best guess.

IIRC™, this has been happening from day 1 when I was given this phone (it was previously sitting unused in a drawer, yay).

> Someone's going to have to dig a Galaxy Note 3 out of a drawer somewhere, go into the archives of old Play Store versions, and try installing them until they find the version that broke it, so anything that makes that binary search process less terrible would be a start.

Oh meep. Of course.

I'd have no problem loaning the device (perhaps the carrier-specific image it's using is implicated), but that's probably a huge pile of overhead to deal with. I wonder if I can help out with the bisection process myself?

Hmm. Given that this is the Play Store and the device is (currently) not rooted, I couldn't do it the "russian" way with random APK sites even if I wanted to.

I'm very curious what the internal path is here - does it depend on rooting or is there a way to isolate devices and send them specific versions of apps?

(Now I'm imagining being given a (bespoke) HTTP endpoint to hit (just for this) to switch versions...)

Maybe the best path forward would just be to root this thing already. I'd be very surprised if rooting affected the situation.

Thanks very much for the thought about bisecting GPS though. Definitely hadn't thought of that myself at this point, and don't think I would have anytime soon.


We just used adb install. It might've involved installing a special version of Android, but I deliberately forgot about that process because it sucked. Either way, I'd be kind of surprised if Play wasn't a special case, no clue what they do. (I'm no longer at Google, can't even check.)

Good luck with your quest though!


> I'd be kind of surprised if Play wasn't a special case

It probably is, but there's also the

  Failure [INSTALL_FAILED_ALREADY_EXISTS]
brick wall which makes perfect sense, is not especially specific to the Play Store, and will likely require root (then some careful `mv`s) to squish. Yayyy.

> Good luck with your quest though!

Much appreciated :) thanks again for the insight/feedback!




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