public virtual in PyROOT

From: OKUMURA, Akira <oxon_at_astro.isas.jaxa.jp>
Date: Tue, 3 Aug 2010 16:52:06 -0700

Hello ROOTers,

When I use a ROOT based class in PyROOT, I get a seg fault. The class derives from TNamed but I use "public virtual TNamed" instead of "public TNamed" to avoid multiple inheritance. I would like to know how to work around this problem. I am using Python 2.6.1 and GCC 4.2.1 on OS X 10.6.4 and ROOT 5.27.02.

The attached is a minimum example. The following are ROOT and PyROOT examples.

• ROOT interpreter (OK) === [oxon_at_kusu ~]$ root root [0] .L test.C+ root [1] TMyClass my root [2] my.GetNamed()->SetName("name") root [3] my.GetNamed()->GetName() (const char* 0x103b54e18)"name"
• Python interpreter (NG) === [oxon_at_kusu ~]$ python Python 2.6.1 (r261:67515, Feb 11 2010, 00:51:29) [GCC 4.2.1 (Apple Inc. build 5646)] on darwin Type "help", "copyright", "credits" or "license" for more information. >>> import ROOT >>> ROOT.gROOT.ProcessLine(".L test.C+") 0L >>> my = ROOT.TMyClass() >>> my.GetNamed()
  • Break *** segmentation violation

    ---

There was a crash.
This is the entire stack trace of all threads:

---

Thread 2 (process 35270):
#0 0x00007fff83e14eb6 in __semwait_signal ()
#1 0x00007fff83e18cd1 in _pthread_cond_wait ()
#2 0x00000001000adcea in PyThread_acquire_lock ()
#3 0x00000001000852e4 in PyEval_RestoreThread ()
#4 0x00000001048c5ff5 in _PyTime_DoubleToTimet ()
#5 0x0000000100089187 in PyEval_EvalFrameEx ()
#6 0x000000010008acce in PyEval_EvalCodeEx ()
#7 0x000000010002c88f in PyClassMethod_New ()
#8 0x000000010000aff3 in PyObject_Call ()
#9 0x000000010008a54e in PyEval_EvalFrameEx ()
#10 0x00000001000892e1 in PyEval_EvalFrameEx ()
#11 0x00000001000892e1 in PyEval_EvalFrameEx ()
#12 0x000000010008acce in PyEval_EvalCodeEx ()
#13 0x000000010002c8e1 in PyClassMethod_New ()
#14 0x000000010000aff3 in PyObject_Call ()
#15 0x000000010001a9df in PyClass_New ()
#16 0x000000010000aff3 in PyObject_Call ()
#17 0x00000001000849db in PyEval_CallObjectWithKeywords ()
#18 0x00000001000b1db6 in initthread ()
#19 0x00007fff83e13456 in _pthread_start ()
#20 0x00007fff83e13309 in thread_start ()

Thread 1 (process 35270):
#0 0x00007fff83e57c90 in wait4 ()
#1 0x00007fff83e6c23e in system ()
#2 0x00000001011c4488 in TUnixSystem::StackTrace ()
#3 0x00000001011c1e0a in TUnixSystem::DispatchSignals ()
#4 <signal handler called>
#5 0x0000000101013aa7 in PyROOT::TMemoryRegulator::RegisterObject ()
#6 0x000000010102ab98 in PyROOT::BindRootObject ()
#7 0x0000000101016df2 in PyROOT::TMethodHolder<PyROOT::TScopeAdapter, PyROOT::TMemberAdapter>::CallSafe ()
#8 0x0000000101016fa6 in PyROOT::TMethodHolder<PyROOT::TScopeAdapter, PyROOT::TMemberAdapter>::Execute ()
#9 0x0000000101014815 in PyROOT::TMethodHolder<PyROOT::TScopeAdapter, PyROOT::TMemberAdapter>::operator() ()
#10 0x000000010101bd12 in PyROOT::(anonymous namespace)::mp_call ()
#11 0x000000010000aff3 in PyObject_Call ()
#12 0x000000010008a51a in PyEval_EvalFrameEx ()
#13 0x000000010008acce in PyEval_EvalCodeEx ()
#14 0x000000010008ad61 in PyEval_EvalCode ()
#15 0x00000001000a265a in Py_CompileString ()
#16 0x00000001000a44dd in PyRun_InteractiveOneFlags ()
#17 0x00000001000a4615 in PyRun_InteractiveLoopFlags ()
#18 0x00000001000a4685 in PyRun_AnyFileExFlags ()
#19 0x00000001000b0286 in Py_Main ()
#20 0x0000000100000e6c in start ()

---

The lines below might hint at the cause of the crash. If they do not help you then please submit a bug report at http://root.cern.ch/bugs. Please post the ENTIRE stack trace from above as an attachment in addition to anything else that might help us fixing this issue.

---

#5 0x0000000101013aa7 in PyROOT::TMemoryRegulator::RegisterObject ()
#6 0x000000010102ab98 in PyROOT::BindRootObject ()
#7 0x0000000101016df2 in PyROOT::TMethodHolder<PyROOT::TScopeAdapter, PyROOT::TMemberAdapter>::CallSafe ()
#8 0x0000000101016fa6 in PyROOT::TMethodHolder<PyROOT::TScopeAdapter, PyROOT::TMemberAdapter>::Execute ()
#9 0x0000000101014815 in PyROOT::TMethodHolder<PyROOT::TScopeAdapter, PyROOT::TMemberAdapter>::operator() ()
#10 0x000000010101bd12 in PyROOT::(anonymous namespace)::mp_call ()
#11 0x000000010000aff3 in PyObject_Call ()
#12 0x000000010008a51a in PyEval_EvalFrameEx ()
#13 0x000000010008acce in PyEval_EvalCodeEx ()
#14 0x000000010008ad61 in PyEval_EvalCode ()
#15 0x00000001000a265a in Py_CompileString ()
#16 0x00000001000a44dd in PyRun_InteractiveOneFlags ()
#17 0x00000001000a4615 in PyRun_InteractiveLoopFlags ()
#18 0x00000001000a4685 in PyRun_AnyFileExFlags ()
#19 0x00000001000b0286 in Py_Main ()
#20 0x0000000100000e6c in start ()

---

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
SystemError: problem in C++; program state has been reset

Regards,

--
OKUMURA, Akira oxon@{astro.isas.jaxa.jp,stanford.edu}
Institute of Space and Astronautical Science (ISAS/JAXA)
Now at KIPAC/SLAC/Stanford
Varian Physics #306
382 Via Pueblo Mall, MC 406 Stanford, CA94305
TEL 650-736-0971/FAX 650-724-5065
Skype : okumura.akira






application/octet-stream attachment: test.C

Received on Wed Aug 04 2010 - 01:52:23 CEST