[Qt-interest] Qt x64 Mac Cocoa app crashing randomly (4.6.2)

[Paul Miller]

I've been playing around with the 64-bit Cocoa Qt build on Mac and I'm 
seeing some very odd random crashes.

My app will work once or twice a couple of times. Then it may crash on 
launch the next time, or crash on exit, then it'll work again.

The crashes are "way down" in Qt. When it crashes on startup, it's 
crashing in QHashData::resize(), or maybe in the initial event 
dispatching in QCoreApplication::exec(). When it crashes on exit, it's 
usually in some QWidget clean up code.

It's like memory is getting corrupted somewhere. But, and here's the 
weird thing, when compiled in 32-bit, it works perfectly.

My code is 64-bit clean, as the 64-bit version of the same app on 
Windows works with no problems.

Anyone ever seen anything like this? Unfortunately, my app is pretty 
"big", so I suspect attempting to write a small test case with source 
won't work.