Hi,

I have a 2D game framework for a variety of platforms, now I'm trying to create a osx ".framework". I think I was successful, but there is a weird problem that I need help and I think can be related to the .framework configuration/building.

First, the code was created to be static linked only, now we are in the process of open-sourcing it and I would like to generate dynamic linked objects (.framework for osx, .so for linux, .dll for windows).

I created a test case to use this .framework, and with the first case it worked. Then I added more things in the test case class and then I receive weird crashes.

Basically, my test case is a main and a class with some attributes (none pointer - only objects). When I added 2-3 new attributes, it stop working (sizeof this MyClass is about 14xx bytes).

The main is like this:


Using the second test case MyClass If I add something at the position marked with 1 and add breakpoint it runs to the breakpoint but when trying to step over 2 it will crash, it really looks like some kind of stack corruption when trying to create class object (maybe inside the framework?).

Anybody has any clue of what I'm facing here?
I will try to collect more information about the process running and post as I get at my work.

Thank you

Not much to go on. What does the crash report look like?

Console output when using Debugger:


This class works:


This class crash:


And here, another sample that does not crash:


Facts:
1. The framework reimplement new/delete. But In my sample code I does not do explicit calls to new/delete - still this is a possible cause.
2. The total value to cause a crash when using some .framework class (eg. Sprite in the above class) is 2881+ - that is, If the size of class is (until the creation of any framework object) 2880 or less it doesn't crash.

I will create now a statically linked project with the framework code and see what happens.

Thanks

I have tried using a libSDK.a created using CMake and it works, I have also tried to add cpp/h from library directly inside sample application project and the crash persist.

I will do some more testing with different project structures and configuration.

But, I still prefer creating a Framework, as it will respect my LGPL licensing and is easier to MacOSX developers.

The only two things that jump out at me are:

1) Allocating 2900 bytes on the stack with a single object seems possibly a bad idea.

2) The stack trace shows MyGame() and SDK::Timeline::Timeline() being called and yet you didn't post that code.

My only guess so far is that you're simply blowing the stack space, but I wouldn't feel confident in trying to figure out what the problem is without knowing what that code is doing.

I have my doubts that this has anything to do with using a framework, but I'm not an expert on the dynamic linker and the limits of static allocations etc.

On Linux and Windows, our stack consumption is not a problem. We have a lot more than that in the stack btw.

These two constructors does nothing special:


About the crash at Timeline::Timeline() constructor, that is totally random. If I change the class size to 2890 it will crash in another place, if 2900 then yet another place. It really looks to a .framework configuration problem, as I said, using a static lib linked all works fine.

AFAIK BSD limits the stack size to 8MB by default, up to a maximum of 64MB (http://homepage.mac.com/eric.c/hpc/conte...OS%20X.pdf). Linux allows the stack to grow to the total system memory space if you want it to. I'm not sure what it is on Windows, but given this behavior I'll bet that it can grow the stack to something larger.

If you were using a 64-bit program it'd have a larger stack size from what I've read. (Your debugging output indicates that it's in 32-bit mode).

So, heap allocate that object and keep references to it using smart pointers and you should be good to go. (Though you will have to remember to release it when you're done with it). http://www.boost.org/doc/libs/1_42_0/lib...rt_ptr.htm

Mac OS X uses an 8M stack for the main thread and 512K stacks for secondary threads IIRC. You can also request larger stacks (for your main thread, at link time, for pthreads, at pthread creation time).

It seems unlikely that static vs. dynamic linking could change that...

I created again the project from nothing and now everything is working, I have no idea about what was happening.

Thanks