Segfault during loopsigma

[mbudisic]

This has happened multiple times this afternoon, once on a trajectory braid I am working on, once during running of the braidlab testsuite. It looks like it will require some deep debugging of loopsigma code (see frame [8] in the stack):

MATLAB crash file:/Users/marko/matlab_crash_dump.8541-1:

------------------------------------------------------------------------
       Segmentation violation detected at Tue Oct  6 17:26:02 2015
------------------------------------------------------------------------

Configuration:
  Crash Decoding      : Disabled
  Crash Mode          : continue (default)
  Current Graphics Driver: Unknown hardware 
  Current Visual      : Quartz
  Default Encoding    : ISO-8859-1
  Host Name           : marko-lt
  MATLAB Architecture : maci64
  MATLAB Root         : /Applications/MATLAB_R2015b.app
  MATLAB Version      : 8.6.0.267246 (R2015b)
  OpenGL              : hardware
  Operating System    : Darwin 14.5.0 Darwin Kernel Version 14.5.0: Wed Jul 29 02:26:53 PDT 2015; root:xnu-2782.40.9~1/RELEASE_X86_64 x86_64
  Processor ID        : x86 Family 6 Model 58 Stepping 9, GenuineIntel
  Virtual Machine     : Java 1.7.0_75-b13 with Oracle Corporation Java HotSpot(TM) 64-Bit Server VM mixed mode
  Window System       : Quartz

Fault Count: 1

Abnormal termination:
Segmentation violation

Register State (from fault):
  RAX = 00007ff5e61614a0  RBX = 000000011838ba78
  RCX = 000000010a90e000  RDX = 0000000000000048
  RSP = 0000000000000048  RBP = 000000010a9c9000
  RSI = 00007fff8a40a667  RDI = 0000000132b76d20

   R8 = 000000011838bad0   R9 = 0000000132b77000
  R10 = 0000000132b76d40  R11 = 00007fff8a409187
  R12 = 0000000132b77000  R13 = 0000000000000048
  R14 = 00007ff5e5f07d60  R15 = 00007ff5e5f07d60

  RIP = 000000011838bad0  RFL = 00007ff5e5f07d78

   CS = 0000000132b76d90   FS = 000000012d250b40   GS = 0000000132b77000

Stack Trace (from fault):
[  0] 0x000000010cd66a34 /Applications/MATLAB_R2015b.app/bin/maci64/libmwfl.dylib+00027188 _ZN2fl4diag15stacktrace_base7captureERKNS0_14thread_contextEm+00000052
[  1] 0x000000010cd6a35a /Applications/MATLAB_R2015b.app/bin/maci64/libmwfl.dylib+00041818 _ZN2fl4test17terminate_handledEv+00000746
[  2] 0x000000010cd69e08 /Applications/MATLAB_R2015b.app/bin/maci64/libmwfl.dylib+00040456 _ZN2fl4diag13terminate_logEPKcPK17__darwin_ucontext+00000152
[  3] 0x000000010eac3316 /Applications/MATLAB_R2015b.app/bin/maci64/libmwmcr.dylib+00336662 _Z32mnRunPathDependentInitializationv+00002806
[  4] 0x000000010eac35a9 /Applications/MATLAB_R2015b.app/bin/maci64/libmwmcr.dylib+00337321 _Z32mnRunPathDependentInitializationv+00003465
[  5] 0x000000010eac18ca /Applications/MATLAB_R2015b.app/bin/maci64/libmwmcr.dylib+00329930 mnFatalSignalHandler+00000282
[  6] 0x00007fff8b7caf1a           /usr/lib/system/libsystem_platform.dylib+00020250 _sigtramp+00000026
[  7] 0x0000000000000000                                   <unknown-module>+00000000
[  8] 0x000000012d250b40 /Users/marko/Work/MatlabToolbox/braidlab/+braidlab/@braid/private/loopsigma_helper.mexmaci64+00027456 _ZNSt3__113unordered_mapINS_11__thread_idENS_4pairINS_6vectorIiNS_9allocatorIiEEEES6_EENS_4hashIS1_EENS_8equal_toIS1_EENS4_INS2_IKS1_S7_EEEEEixEOS1_+00000272
[  9] 0x000000012d250668 /Users/marko/Work/MatlabToolbox/braidlab/+braidlab/@braid/private/loopsigma_helper.mexmaci64+00026216 _ZN12BraidInPlaceIiE11applyToLoopEm+00000072
[ 10] 0x000000012d24e960 /Users/marko/Work/MatlabToolbox/braidlab/+braidlab/@braid/private/loopsigma_helper.mexmaci64+00018784 _ZNSt3__113packaged_taskIFvvEEclEv+00000080
[ 11] 0x000000012d24d9ef /Users/marko/Work/MatlabToolbox/braidlab/+braidlab/@braid/private/loopsigma_helper.mexmaci64+00014831 _ZZN10ThreadPoolC1EmENKUlvE_clEv+00000511
[ 12] 0x000000012d24d7b0 /Users/marko/Work/MatlabToolbox/braidlab/+braidlab/@braid/private/loopsigma_helper.mexmaci64+00014256 _ZNSt3__114__thread_proxyINS_5tupleIJZN10ThreadPoolC1EmEUlvE_EEEEEPvS5_+00000096
[ 13] 0x00007fff83d4b05a            /usr/lib/system/libsystem_pthread.dylib+00016474 _pthread_body+00000131
[ 14] 0x00007fff83d4afd7            /usr/lib/system/libsystem_pthread.dylib+00016343 _pthread_body+00000000
[ 15] 0x00007fff83d483ed            /usr/lib/system/libsystem_pthread.dylib+00005101 thread_start+00000013

If this problem is reproducible, please submit a Service Request via:
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A technical support engineer might contact you with further information.

Thank you for your help.

[jeanluct]

Darn!

[mbudisic]

I'll close this for now, as I cannot reproduce the error anymore, but since the error is in the parallel resource, it might not be easily reproducible.