Large ROOT application intermittently crashes in TList()

ROOT
1

Hello ROOTers,

We have a rather large VS2008 C++ application using ROOT 5.28, on a Win32 system. It collects data from several USB DAQ devices and a custom fpga, and continuously displays several plots of the data.

One site has intermittent crashes; it typically crashes about once a day. Using a BugTrap facility, I intercept the crash and write out a dump file. Many of the dumps show this stack trace:

Genesis2.exe caused ACCESS_VIOLATION in module “C:\root\bin\libCore.dll” at 001B:01007F35, TList::FindLink()+53 byte(s)

“C:\root\bin\libCore.dll” at 001B:01007F35, TList::FindLink()+53 byte(s)
“C:\root\bin\libCore.dll” at 001B:010080DE, TList::Remove()+30 byte(s)
“C:\root\bin\libCore.dll” at 001B:01006993, THashList::Remove()+35 byte(s)
“C:\root\bin\libCore.dll” at 001B:00FC41B4, TObjectSpy::~TObjectSpy()+100 byte(s)
“C:\root\bin\libGui.dll” at 001B:01C14EF1, TGClient::HandleEvent()+225 byte(s)
“C:\root\bin\gdk-1.3.dll” at 001B:05FF280D, gdk_event_free()+221 byte(s)

Can you help provide some clues how to debug and resolve this?
I could provide you with the crashdump (8megs) and our symbol files.

thank you very much,
buddy

2

Hi buddy,

Well, I think the only way to debug this would be to attach the debugger when the application crashes, if you are using the debug version of ROOT…

Cheers, Bertrand.

3

This looks like a potential thread-safety issue… would be useful to compile the application with debug information (I’m not sure how to do that in Windows though…) and see if you can get a longer stack trace.