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How to properly report crashes/bugs for iOS build? - Printable Version

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How to properly report crashes/bugs for iOS build? - StoneCut - 10-20-2014 09:10 AM

Hi,

I experience a lot of crashes using the iOS build (no matter which version - up to DEV-Latest) on a jailbroken iPad 2. I need to try to launch a game up to 10 times and then it finally works. When it works, it works pretty great! I don't have these issues using the Windows version.

Anyway, what's the best way to report these issues? I have the iOS "CrashReporter" installed and it writes logs every time PPSSPP crashes. From what I understand see it tries to access illegal RAM pages or something like that. The PPSPP settings themselves don't seem to influence it very much - no matter what I choose I always have the same error and even the same offset.

Would the "CrashReporter" logs be useful for finding and fixing the issue? What else can I do to help the devs?

Also - what's the best way to report more general issues? For example, certain audio parts in Loco Roco don't work.


RE: How to properly report crashes/bugs for iOS build? - [Unknown] - 10-21-2014 01:56 AM

As far as we know, there's some sort of problem with memory management. We ask the operating system for a decently large chunk of address space, and then allocate a small portion of that.

But, based on various tests people have done, it seems like these allocations / address space sometimes unexpectedly overlap system memory or later allocated memory. When this happens, things turn into fireworks.

My suspicion is that mmap() is simply untrustworthy on iOS in the way we're using it, or that the system automatically ditches it on memory pressure or something. If that's the case, it's a problem, because the way we manage memory in PPSSPP is very relied upon in many places (like jit), and pretty crucial to performance.

So, what we really need is someone with time, dedication, and a Mac with a good dev environment to figure out what's going on or if there's some workaround that doesn't require rebuilding memory access just for iOS, and making all platforms significantly slower in the process.

Searching is a great thing to do when reporting issues. For example, that issue has already been reported:
https://github.com/hrydgard/ppsspp/issues/6626
(Google: loco roco music issue ppsspp)

-[Unknown]


RE: How to properly report crashes/bugs for iOS build? - StoneCut - 10-21-2014 11:43 AM

Hi [Unknown],

I'm sorry that I didn't search correctly for the LocoRoco problem when posting - I later discovered the Issue Tracker on GitHub.

Back to the memory problem - is it possible to run PPSSPP in a sort of debug mode so that a comparison of failing runs and those where launching a game actually works can be made which might lead to determine a reliable address space for iOS? I figure a compilation parameter/definition for iOS would be possible so that any sort of workaround would not effect the remaining ports. Maybe I'm thinking to simple here, though.

Unfortunately, I won't be able to track down the problem properly - I could probably set up the develop environment and even compile PPSPP given a certain degree of Unix/Linux experience but then I wouldn't know how to do the actual debugging since I'm not a programmer.


RE: How to properly report crashes/bugs for iOS build? - StoneCut - 11-06-2014 10:03 AM

I'm happy to report that upgrading my iPad2 to iOS 8.1 and jailbreaking with the latest Pangu resolved these issues completely. I can launch games without any crashes every single time. No more memory problems (using "latest" from Cydia).

Now I'm patiently waiting for the fixed build with iPhone 6 Plus screen resolution support Smile