Segmentation fault in face iterator

[kliem]

A patchbots is reporting consistent segmentation faults with combinatorial polyhedron:

E.g.

https://patchbot.sagemath.org/log/32788/Linux/1_SMP_Debian_5.10.70-1_(2021-09-30)/x86_64/5.10.0-9-amd64/tmonteil-lxc1/2021-10-30%2023:39:45

https://patchbot.sagemath.org/log/32777/Linux/1_SMP_Debian_5.10.70-1_(2021-09-30)/x86_64/5.10.0-9-amd64/tmonteil-lxc3/2021-11-04%2016:33:47

CC: @sagetrac-tmonteil @tscrim @vbraun

Component: geometry

Author: Jonathan Kliem

Branch: cdafc5c

Reviewer: Matthias Koeppe, Thierry Monteil

Issue created by migration from https://trac.sagemath.org/ticket/32827

[kliem]

comment:1

@sagetrac-tmonteil:

Could you perhaps inspect that bot and the sage version, if it is still running. It could be a bug with #32666 or a bug that shows now, because something is compiled differently, due to code change.

Either way, it would greatly help, if you could inspect a few things:

Does this work:

sage: Asso = polytopes.associahedron(['A',3])
sage: Asso.vertex_adjacency_matrix()
[0 1 0 0 0 1 0 0 1 0 0 0 0 0]
[1 0 1 0 0 0 0 1 0 0 0 0 0 0]
[0 1 0 1 0 1 0 0 0 0 0 0 0 0]
[0 0 1 0 1 0 0 0 0 0 0 1 0 0]
[0 0 0 1 0 0 0 1 0 0 0 0 1 0]
[1 0 1 0 0 0 0 0 0 0 0 0 0 1]
[0 0 0 0 0 0 0 1 1 0 1 0 0 0]
[0 1 0 0 1 0 1 0 0 0 0 0 0 0]
[1 0 0 0 0 0 1 0 0 1 0 0 0 0]
[0 0 0 0 0 0 0 0 1 0 1 0 0 1]
[0 0 0 0 0 0 1 0 0 1 0 0 1 0]
[0 0 0 1 0 0 0 0 0 0 0 0 1 1]
[0 0 0 0 1 0 0 0 0 0 1 1 0 0]
[0 0 0 0 0 1 0 0 0 1 0 1 0 0]

I guess not.

Now, the combinatorial polyhedron is probably still obtained fine:

sage: Asso = polytopes.associahedron(['A',3])
sage: C = Asso.combinatorial_polyhedron()

Once you have it, there are a number of things to test:

sage: C.edges()

sage: for f in C.face_iter():
....:     print(f)

Same for C.face_iter(dual=True), C.face_iter(0), C.face_iter(0, dual=True).

It should help a lot in catching that bug, seeing exactly when there is a segmentation fault.

Please do not recompile, as the bug might hide then. But I don't know.

[kliem]

Description changed:

--- 
+++ 
@@ -1,7 +1,7 @@
-Some patchbots are reporting consistent segmentation faults with combinatorial polyhedron:
+A patchbots is reporting consistent segmentation faults with combinatorial polyhedron:
 
 E.g.
 
 https://patchbot.sagemath.org/log/32788/Linux/1_SMP_Debian_5.10.70-1_(2021-09-30)/x86_64/5.10.0-9-amd64/tmonteil-lxc1/2021-10-30%2023:39:45
 
-
+https://patchbot.sagemath.org/log/32777/Linux/1_SMP_Debian_5.10.70-1_(2021-09-30)/x86_64/5.10.0-9-amd64/tmonteil-lxc3/2021-11-04%2016:33:47

[sagetrac-tmonteil]

comment:2

Replying to @kliem:

@sagetrac-tmonteil:

Could you perhaps inspect that bot and the sage version, if it is still running. It could be a bug with #32666 or a bug that shows now, because something is compiled differently, due to code change.

Either way, it would greatly help, if you could inspect a few things:

Does this work:

On the current state of tmonteil-lxc1, wich is a merge between 9.5.beta5 and the branch of #32320 i do not have any error.

On tmonteil-lxc3, which is a merge between 9.5.beta5 and the branch of #31635, i have:

sage: Asso = polytopes.associahedron(['A',3])
sage: Asso.vertex_adjacency_matrix()
[0 1 0 0 0 1 0 0 1 0 0 0 0 0]
[1 0 1 0 0 0 0 1 0 0 0 0 0 0]
[0 1 0 1 0 1 0 0 0 0 0 0 0 0]
[0 0 1 0 1 0 0 0 0 0 0 1 0 0]
[0 0 0 1 0 0 0 1 0 0 0 0 1 0]
[1 0 1 0 0 0 0 0 0 0 0 0 0 1]
[0 0 0 0 0 0 0 1 1 0 1 0 0 0]
[0 1 0 0 1 0 1 0 0 0 0 0 0 0]
[1 0 0 0 0 0 1 0 0 1 0 0 0 0]
[0 0 0 0 0 0 0 0 1 0 1 0 0 1]
[0 0 0 0 0 0 1 0 0 1 0 0 1 0]
[0 0 0 1 0 0 0 0 0 0 0 0 1 1]
[0 0 0 0 1 0 0 0 0 0 1 1 0 0]
[0 0 0 0 0 1 0 0 0 1 0 1 0 0]

I guess not.

Indeed:

sage: Asso = polytopes.associahedron(['A',3])
sage: Asso.vertex_adjacency_matrix()
------------------------------------------------------------------------
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/cysignals/signals.cpython-37m-x86_64-linux-gnu.so(+0x947b)[0x7f2d6c21947b]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/cysignals/signals.cpython-37m-x86_64-linux-gnu.so(+0xf2d8)[0x7f2d6c21f2d8]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/cysignals/signals.cpython-37m-x86_64-linux-gnu.so(+0xfff0)[0x7f2d6c21fff0]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x12730)[0x7f2d6fc47730]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/face_iterator.cpython-37m-x86_64-linux-gnu.so(+0xe4d0)[0x7f2d112f54d0]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/face_iterator.cpython-37m-x86_64-linux-gnu.so(+0x14466)[0x7f2d112fb466]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/base.cpython-37m-x86_64-linux-gnu.so(+0x1d3d2)[0x7f2d113723d2]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/base.cpython-37m-x86_64-linux-gnu.so(+0x1f1d7)[0x7f2d113741d7]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/base.cpython-37m-x86_64-linux-gnu.so(+0x49d7b)[0x7f2d1139ed7b]
python3(_PyMethodDef_RawFastCallDict+0x22a)[0x5d8c6a]
python3[0x4d743e]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/misc/cachefunc.cpython-37m-x86_64-linux-gnu.so(+0x134cd)[0x7f2d6cdb64cd]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/misc/cachefunc.cpython-37m-x86_64-linux-gnu.so(+0x287eb)[0x7f2d6cdcb7eb]
python3(_PyObject_FastCallKeywords+0x4eb)[0x5da01b]
python3[0x54b3c1]
python3(_PyEval_EvalFrameDefault+0x441d)[0x5524cd]
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/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/misc/cachefunc.cpython-37m-x86_64-linux-gnu.so(+0x10dba)[0x7f2d6cdb3dba]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/misc/cachefunc.cpython-37m-x86_64-linux-gnu.so(+0x287d0)[0x7f2d6cdcb7d0]
python3(_PyObject_FastCallKeywords+0x4eb)[0x5da01b]
python3[0x54b3c1]
python3(_PyEval_EvalFrameDefault+0x441d)[0x5524cd]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3[0x558f25]
python3(_PyMethodDef_RawFastCallKeywords+0x1b3)[0x5d8833]
python3(_PyEval_EvalFrameDefault+0x42c3)[0x552373]
python3[0x4d37a6]
python3(_PyEval_EvalFrameDefault+0x1a75)[0x54fb25]
python3[0x4d37a6]
python3(_PyEval_EvalFrameDefault+0x1a75)[0x54fb25]
python3[0x4d37a6]
python3(_PyMethodDescr_FastCallKeywords+0x151)[0x4d76a1]
python3(_PyEval_EvalFrameDefault+0x45f8)[0x5526a8]
python3(_PyFunction_FastCallKeywords+0x18c)[0x5d91fc]
python3(_PyEval_EvalFrameDefault+0x4fc)[0x54e5ac]
python3(_PyFunction_FastCallKeywords+0x18c)[0x5d91fc]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(_PyFunction_FastCallKeywords+0x482)[0x5d94f2]
python3[0x54b1f0]
python3(_PyEval_EvalFrameDefault+0x13ae)[0x54f45e]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(_PyFunction_FastCallKeywords+0x482)[0x5d94f2]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(_PyFunction_FastCallKeywords+0x482)[0x5d94f2]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyFunction_FastCallKeywords+0x18c)[0x5d91fc]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(PyEval_EvalCode+0x23)[0x54e0a3]
python3[0x630ce2]
python3(PyRun_FileExFlags+0x97)[0x630d97]
python3(PyRun_SimpleFileExFlags+0x17f)[0x6319ff]
python3[0x65432e]
python3(_Py_UnixMain+0x2e)[0x65468e]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xeb)[0x7f2d6f6ae09b]
python3(_start+0x2a)[0x5e0e8a]
------------------------------------------------------------------------
Attaching gdb to process id 1024695.
Cannot find gdb installed
GDB is not installed.
Install gdb for enhanced tracebacks.
------------------------------------------------------------------------
Unhandled SIGSEGV: A segmentation fault occurred.
This probably occurred because a *compiled* module has a bug
in it and is not properly wrapped with sig_on(), sig_off().
Python will now terminate.
------------------------------------------------------------------------
Segmentation fault

Now, the combinatorial polyhedron is probably still obtained fine:

sage: Asso = polytopes.associahedron(['A',3])
sage: C = Asso.combinatorial_polyhedron()

Once you have it, there are a number of things to test:

sage: C.edges()

sage: Asso = polytopes.associahedron(['A',3])
sage: C = Asso.combinatorial_polyhedron()
sage: C.edges()
------------------------------------------------------------------------
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/cysignals/signals.cpython-37m-x86_64-linux-gnu.so(+0x947b)[0x7f4e6052547b]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/cysignals/signals.cpython-37m-x86_64-linux-gnu.so(+0xf2d8)[0x7f4e6052b2d8]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/cysignals/signals.cpython-37m-x86_64-linux-gnu.so(+0xfff0)[0x7f4e6052bff0]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x12730)[0x7f4e63513730]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/face_iterator.cpython-37m-x86_64-linux-gnu.so(+0xe4d0)[0x7f4e04bc24d0]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/face_iterator.cpython-37m-x86_64-linux-gnu.so(+0x14466)[0x7f4e04bc8466]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/base.cpython-37m-x86_64-linux-gnu.so(+0x1d3d2)[0x7f4e04c3f3d2]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/base.cpython-37m-x86_64-linux-gnu.so(+0x1f1d7)[0x7f4e04c411d7]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/base.cpython-37m-x86_64-linux-gnu.so(+0x4d73d)[0x7f4e04c6f73d]
python3(_PyMethodDescr_FastCallKeywords+0x3c4)[0x4d7914]
python3(_PyEval_EvalFrameDefault+0x45f8)[0x5526a8]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3[0x558f25]
python3(_PyMethodDef_RawFastCallKeywords+0x1b3)[0x5d8833]
python3(_PyEval_EvalFrameDefault+0x42c3)[0x552373]
python3[0x4d37a6]
python3(_PyEval_EvalFrameDefault+0x1a75)[0x54fb25]
python3[0x4d37a6]
python3(_PyEval_EvalFrameDefault+0x1a75)[0x54fb25]
python3[0x4d37a6]
python3(_PyMethodDescr_FastCallKeywords+0x151)[0x4d76a1]
python3(_PyEval_EvalFrameDefault+0x45f8)[0x5526a8]
python3(_PyFunction_FastCallKeywords+0x18c)[0x5d91fc]
python3(_PyEval_EvalFrameDefault+0x4fc)[0x54e5ac]
python3(_PyFunction_FastCallKeywords+0x18c)[0x5d91fc]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(_PyFunction_FastCallKeywords+0x482)[0x5d94f2]
python3[0x54b1f0]
python3(_PyEval_EvalFrameDefault+0x13ae)[0x54f45e]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(_PyFunction_FastCallKeywords+0x482)[0x5d94f2]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(_PyFunction_FastCallKeywords+0x482)[0x5d94f2]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyFunction_FastCallKeywords+0x18c)[0x5d91fc]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(PyEval_EvalCode+0x23)[0x54e0a3]
python3[0x630ce2]
python3(PyRun_FileExFlags+0x97)[0x630d97]
python3(PyRun_SimpleFileExFlags+0x17f)[0x6319ff]
python3[0x65432e]
python3(_Py_UnixMain+0x2e)[0x65468e]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xeb)[0x7f4e62f7a09b]
python3(_start+0x2a)[0x5e0e8a]
------------------------------------------------------------------------
Attaching gdb to process id 1024859.
Cannot find gdb installed
GDB is not installed.
Install gdb for enhanced tracebacks.
------------------------------------------------------------------------
Unhandled SIGSEGV: A segmentation fault occurred.
This probably occurred because a *compiled* module has a bug
in it and is not properly wrapped with sig_on(), sig_off().
Python will now terminate.
------------------------------------------------------------------------
Segmentation fault

sage: for f in C.face_iter():
....:     print(f)

sage: Asso = polytopes.associahedron(['A',3])
sage: C = Asso.combinatorial_polyhedron()
sage: for f in C.face_iter():
....:     print(f)
....: 
------------------------------------------------------------------------
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/cysignals/signals.cpython-37m-x86_64-linux-gnu.so(+0x947b)[0x7f31646b547b]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/cysignals/signals.cpython-37m-x86_64-linux-gnu.so(+0xf2d8)[0x7f31646bb2d8]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/cysignals/signals.cpython-37m-x86_64-linux-gnu.so(+0xfff0)[0x7f31646bbff0]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x12730)[0x7f31676a3730]
/lib/x86_64-linux-gnu/libc.so.6(+0x15cb0d)[0x7f3167242b0d]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/combinatorial_face.cpython-37m-x86_64-linux-gnu.so(+0x1305a)[0x7f3108d8b05a]
python3[0x599551]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/face_iterator.cpython-37m-x86_64-linux-gnu.so(+0xc9ac)[0x7f3108d529ac]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/face_iterator.cpython-37m-x86_64-linux-gnu.so(+0x15948)[0x7f3108d5b948]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/face_iterator.cpython-37m-x86_64-linux-gnu.so(+0x1a2ef)[0x7f3108d602ef]
python3(_PyEval_EvalFrameDefault+0x8cd)[0x54e97d]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3[0x558f25]
python3(_PyMethodDef_RawFastCallKeywords+0x1b3)[0x5d8833]
python3(_PyEval_EvalFrameDefault+0x42c3)[0x552373]
python3[0x4d37a6]
python3(_PyEval_EvalFrameDefault+0x1a75)[0x54fb25]
python3[0x4d37a6]
python3(_PyEval_EvalFrameDefault+0x1a75)[0x54fb25]
python3[0x4d37a6]
python3(_PyMethodDescr_FastCallKeywords+0x151)[0x4d76a1]
python3(_PyEval_EvalFrameDefault+0x45f8)[0x5526a8]
python3(_PyFunction_FastCallKeywords+0x18c)[0x5d91fc]
python3(_PyEval_EvalFrameDefault+0x4fc)[0x54e5ac]
python3(_PyFunction_FastCallKeywords+0x18c)[0x5d91fc]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(_PyFunction_FastCallKeywords+0x482)[0x5d94f2]
python3[0x54b1f0]
python3(_PyEval_EvalFrameDefault+0x13ae)[0x54f45e]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(_PyFunction_FastCallKeywords+0x482)[0x5d94f2]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(_PyFunction_FastCallKeywords+0x482)[0x5d94f2]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyFunction_FastCallKeywords+0x18c)[0x5d91fc]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(PyEval_EvalCode+0x23)[0x54e0a3]
python3[0x630ce2]
python3(PyRun_FileExFlags+0x97)[0x630d97]
python3(PyRun_SimpleFileExFlags+0x17f)[0x6319ff]
python3[0x65432e]
python3(_Py_UnixMain+0x2e)[0x65468e]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xeb)[0x7f316710a09b]
python3(_start+0x2a)[0x5e0e8a]
------------------------------------------------------------------------
Attaching gdb to process id 1025024.
Cannot find gdb installed
GDB is not installed.
Install gdb for enhanced tracebacks.
------------------------------------------------------------------------
Unhandled SIGSEGV: A segmentation fault occurred.
This probably occurred because a *compiled* module has a bug
in it and is not properly wrapped with sig_on(), sig_off().
Python will now terminate.
------------------------------------------------------------------------
Segmentation fault

Same for C.face_iter(dual=True),

sage: Asso = polytopes.associahedron(['A',3])
sage: C = Asso.combinatorial_polyhedron()
sage: for f in C.face_iter(dual=True):
....:     print(f)
....: 
------------------------------------------------------------------------
Segmentation fault

C.face_iter(0),

sage: Asso = polytopes.associahedron(['A',3])
sage: C = Asso.combinatorial_polyhedron()
sage: for f in C.face_iter(0):
....:     print(f)
....: 
A 0-dimensional face of a 3-dimensional combinatorial polyhedron
A 0-dimensional face of a 3-dimensional combinatorial polyhedron
A 0-dimensional face of a 3-dimensional combinatorial polyhedron
A 0-dimensional face of a 3-dimensional combinatorial polyhedron
A 0-dimensional face of a 3-dimensional combinatorial polyhedron
A 0-dimensional face of a 3-dimensional combinatorial polyhedron
A 0-dimensional face of a 3-dimensional combinatorial polyhedron
A 0-dimensional face of a 3-dimensional combinatorial polyhedron
A 0-dimensional face of a 3-dimensional combinatorial polyhedron
A 0-dimensional face of a 3-dimensional combinatorial polyhedron
A 0-dimensional face of a 3-dimensional combinatorial polyhedron
A 0-dimensional face of a 3-dimensional combinatorial polyhedron
A 0-dimensional face of a 3-dimensional combinatorial polyhedron
A 0-dimensional face of a 3-dimensional combinatorial polyhedron

C.face_iter(0, dual=True).

sage: for f in C.face_iter(0, dual=True):
....:     print(f)
....: 
------------------------------------------------------------------------
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/cysignals/signals.cpython-37m-x86_64-linux-gnu.so(+0x947b)[0x7f6886f5547b]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/cysignals/signals.cpython-37m-x86_64-linux-gnu.so(+0xf2d8)[0x7f6886f5b2d8]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/cysignals/signals.cpython-37m-x86_64-linux-gnu.so(+0xfff0)[0x7f6886f5bff0]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x12730)[0x7f688a983730]
/lib/x86_64-linux-gnu/libc.so.6(+0x15cb0d)[0x7f688a522b0d]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/combinatorial_face.cpython-37m-x86_64-linux-gnu.so(+0x1305a)[0x7f682c06a05a]
python3[0x599551]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/face_iterator.cpython-37m-x86_64-linux-gnu.so(+0xc9ac)[0x7f682c0319ac]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/face_iterator.cpython-37m-x86_64-linux-gnu.so(+0x15948)[0x7f682c03a948]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/face_iterator.cpython-37m-x86_64-linux-gnu.so(+0x1a2ef)[0x7f682c03f2ef]
python3(_PyEval_EvalFrameDefault+0x8cd)[0x54e97d]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3[0x558f25]
python3(_PyMethodDef_RawFastCallKeywords+0x1b3)[0x5d8833]
python3(_PyEval_EvalFrameDefault+0x42c3)[0x552373]
python3[0x4d37a6]
python3(_PyEval_EvalFrameDefault+0x1a75)[0x54fb25]
python3[0x4d37a6]
python3(_PyEval_EvalFrameDefault+0x1a75)[0x54fb25]
python3[0x4d37a6]
python3(_PyMethodDescr_FastCallKeywords+0x151)[0x4d76a1]
python3(_PyEval_EvalFrameDefault+0x45f8)[0x5526a8]
python3(_PyFunction_FastCallKeywords+0x18c)[0x5d91fc]
python3(_PyEval_EvalFrameDefault+0x4fc)[0x54e5ac]
python3(_PyFunction_FastCallKeywords+0x18c)[0x5d91fc]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(_PyFunction_FastCallKeywords+0x482)[0x5d94f2]
python3[0x54b1f0]
python3(_PyEval_EvalFrameDefault+0x13ae)[0x54f45e]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(_PyFunction_FastCallKeywords+0x482)[0x5d94f2]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(_PyFunction_FastCallKeywords+0x482)[0x5d94f2]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyFunction_FastCallKeywords+0x18c)[0x5d91fc]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(PyEval_EvalCode+0x23)[0x54e0a3]
python3[0x630ce2]
python3(PyRun_FileExFlags+0x97)[0x630d97]
python3(PyRun_SimpleFileExFlags+0x17f)[0x6319ff]
python3[0x65432e]
python3(_Py_UnixMain+0x2e)[0x65468e]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xeb)[0x7f688a3ea09b]
python3(_start+0x2a)[0x5e0e8a]
------------------------------------------------------------------------
Attaching gdb to process id 1025356.
Cannot find gdb installed
GDB is not installed.
Install gdb for enhanced tracebacks.
------------------------------------------------------------------------
Unhandled SIGSEGV: A segmentation fault occurred.
This probably occurred because a *compiled* module has a bug
in it and is not properly wrapped with sig_on(), sig_off().
Python will now terminate.
------------------------------------------------------------------------
Segmentation fault

It should help a lot in catching that bug, seeing exactly when there is a segmentation fault.

Please do not recompile, as the bug might hide then. But I don't know.

[kliem]

comment:3

Thank you.

That is even worse than I thought, but on the upside this might make debugging easier.

How about:

sage: Asso = polytopes.associahedron(['A',3])
sage: C = Asso.combinatorial_polyhedron()
sage: C.face_iter()
Iterator over the proper faces of a 3-dimensional combinatorial polyhedron

If this works:

sage: Asso = polytopes.associahedron(['A',3])
sage: C = Asso.combinatorial_polyhedron()
sage: it = C.face_iter()
sage: cython('''
....: from sage.geometry.polyhedron.combinatorial_polyhedron.face_iterator cimport FaceIterator
....: def foo(FaceIterator it):
....:     cdef int d = it.next_dimension()
....:     while d < it.structure.dimension:
....:         print(d)
....:         print(it.n_atom_rep())
....:         a = it.set_atom_rep()
....:         print([it.structure.atom_rep[i] for i in range(a)])
....:         b = it.set_coatom_rep()
....:         print([it.structure.coatom_rep[i] for i in range(b)])
....:         d = it.next_dimension()
....: ''')
sage: foo(it)

[sagetrac-tmonteil]

comment:4

On both machines, i got:

sage: sage: Asso = polytopes.associahedron(['A',3])
....: sage: C = Asso.combinatorial_polyhedron()
....: sage: C.face_iter()
Iterator over the proper faces of a 3-dimensional combinatorial polyhedron
sage: sage: Asso = polytopes.associahedron(['A',3])
....: sage: C = Asso.combinatorial_polyhedron()
....: sage: it = C.face_iter()
....: sage: cython('''
....: ....: from sage.geometry.polyhedron.combinatorial_polyhedron.face_iterator cimport FaceIterator
....: ....: def foo(FaceIterator it):
....: ....:     cdef int d = it.next_dimension()
....: ....:     while d < it.structure.dimension:
....: ....:         print(d)
....: ....:         print(it.n_atom_rep())
....: ....:         a = it.set_atom_rep()
....: ....:         print([it.structure.atom_rep[i] for i in range(a)])
....: ....:         b = it.set_coatom_rep()
....: ....:         print([it.structure.coatom_rep[i] for i in range(b)])
....: ....:         d = it.next_dimension()
....: ....: ''')
....: sage: foo(it)
2
5
[0, 5, 8, 9, 13]
[8]
2
4
[6, 8, 9, 10]
[7]
2
5
[4, 6, 7, 10, 12]
[6]
2
4
[3, 4, 11, 12]
[5]




2
5
[9, 10, 11, 12, 13]
[3]
2
5
[2, 3, 5, 11, 13]
[2]
2
4
[0, 1, 2, 5]
[1]
2
5
[1, 2, 3, 4, 7]
[0]
1
2
[8, 9]
[7, 8]
1
2
[0, 8]
[4, 8]
1
2
[9, 13]
[3, 8]
1
2
[5, 13]
[2, 8]
1
2
[0, 5]
[1, 8]
0
1
[8]
[4, 7, 8]
0
1
[9]
[3, 7, 8]
0
1
[0]
[1, 4, 8]
0
1
[13]
[2, 3, 8]
0
1
[5]
[1, 2, 8]
1
2
[6, 10]
[6, 7]
1
2
[6, 8]
[4, 7]
1
2
[9, 10]
[3, 7]
0
1
[6]
[4, 6, 7]
0
1
[10]
[3, 6, 7]
1
2
[4, 12]
[5, 6]
1
2
[6, 7]
[4, 6]
1
2
[10, 12]
[3, 6]
1
2
[4, 7]
[0, 6]
0
1
[12]
[3, 5, 6]
0
1
[4]
[0, 5, 6]
0
1
[7]
[0, 4, 6]
1
2
[11, 12]
[3, 5]
1
2
[3, 11]
[2, 5]
1
2
[3, 4]
[0, 5]
0
1
[11]
[2, 3, 5]
0
1
[3]
[0, 2, 5]
1
2
[0, 1]
[1, 4]
1
2
[1, 7]
[0, 4]
0
1
[1]
[0, 1, 4]
1
2
[11, 13]
[2, 3]
1
2
[2, 5]
[1, 2]
1
2
[2, 3]
[0, 2]
0
1
[2]
[0, 1, 2]
1
2
[1, 2]
[0, 1]

[kliem]

comment:5

Thank you. Apparently the face iterator works and something with CombinatorialFace is failing.

Can you please try the following:

sage: cython('''
....: from sage.geometry.polyhedron.combinatorial_polyhedron.face_list_data_structure cimport *
....: 
....: cdef class foo:
....:     cdef face_t face
....:     cdef MemoryAllocator mem
....:     
....:     def __cinit__(self):
....:         self.mem = MemoryAllocator()
....:         face_init(self.face, 9, 14, self.mem)
....:         
....:     def test(self):
....:         cdef face_t new_face
....:         cdef mem = MemoryAllocator()
....:         print('a')
....:         face_init(new_face, 9, 14, mem)
....:         print('b')
....:         face_copy(self.face, new_face)
....:         
....:     def test2(self):
....:         cdef face_list_t faces
....:         cdef mem = MemoryAllocator()
....:         print('a')
....:         face_list_init(faces, 9, 9, 14, mem)
....:         cdef face_t new_face
....:         for i in range(9):
....:             print(i)
....:             new_face[0] = faces.faces[i][0]
....:             print(i, 'b')
....:             face_copy(self.face, new_face)
....: ''')
sage: a = foo()
sage: a.test()
sage: a.test2()

[sagetrac-tmonteil]

comment:6

I got :

sage: sage: cython('''
....: ....: from sage.geometry.polyhedron.combinatorial_polyhedron.face_list_data_structure cimport *
....: ....: 
....: ....: cdef class foo:
....: ....:     cdef face_t face
....: ....:     cdef MemoryAllocator mem
....: ....:     
....: ....:     def __cinit__(self):
....: ....:         self.mem = MemoryAllocator()
....: ....:         face_init(self.face, 9, 14, self.mem)
....: ....:         
....: ....:     def test(self):
....: ....:         cdef face_t new_face
....: ....:         cdef mem = MemoryAllocator()
....: ....:         print('a')
....: ....:         face_init(new_face, 9, 14, mem)
....: ....:         print('b')
....: ....:         face_copy(self.face, new_face)
....: ....:         
....: ....:     def test2(self):
....: ....:         cdef face_list_t faces
....: ....:         cdef mem = MemoryAllocator()
....: ....:         print('a')
....: ....:         face_list_init(faces, 9, 9, 14, mem)
....: ....:         cdef face_t new_face
....: ....:         for i in range(9):
....: ....:             print(i)
....: ....:             new_face[0] = faces.faces[i][0]
....: ....:             print(i, 'b')
....: ....:             face_copy(self.face, new_face)
....: ....: ''')
....: sage: a = foo()
....: sage: a.test()
....: sage: a.test2()
....: 
a
b
a
0
0 b
1
1 b
2
2 b
3
3 b
4
4 b
5
5 b
6
6 b
7
7 b
8
8 b

[kliem]

comment:7

Ok, thanks. Sorry this is taking so long.

The only thing that I can think of right now, is that one needs to be careful with __cinit__ and __init__.

Can you please try:

sage: cython('''
....: from sage.geometry.polyhedron.combinatorial_polyhedron.face_list_data_structure cimport *
....: 
....: cdef class foo:
....:     cdef face_t face
....:     cdef MemoryAllocator mem
....:     
....:     def __init__(self):
....:         self.mem = MemoryAllocator()
....:         face_init(self.face, 9, 14, self.mem)
....:         
....:     def test(self):
....:         cdef face_t new_face
....:         cdef mem = MemoryAllocator()
....:         print('a')
....:         face_init(new_face, 9, 14, mem)
....:         print('b')
....:         face_copy(self.face, new_face)
....:         
....:     def test2(self):
....:         cdef face_list_t faces
....:         cdef mem = MemoryAllocator()
....:         print('a')
....:         face_list_init(faces, 9, 9, 14, mem)
....:         cdef face_t new_face
....:         for i in range(9):
....:             print(i)
....:             new_face[0] = faces.faces[i][0]
....:             print(i, 'b')
....:             face_copy(self.face, new_face)
....: ''')
sage: a = foo()
sage: a.test()
sage: a.test2()

Also just to confirm:

sage: sage: Asso = polytopes.associahedron(['A',3])
sage: it = Asso.face_generator()
sage: f = next(it)
sage: f
A 3-dimensional face of a Polyhedron in QQ^3 defined as the convex hull of 14 vertices
sage: f = next(it)
sage: f
A -1-dimensional face of a Polyhedron in QQ^3
sage: f = next(it)
sage: f
A 2-dimensional face of a Polyhedron in QQ^3 defined as the convex hull of 5 vertices

And:

sage: Asso = polytopes.associahedron(['A',3])
sage: C = Asso.combinatorial_polyhedron()
sage: it = C.face_iter()
sage: f = next(it)
sage: f
A 2-dimensional face of a 3-dimensional combinatorial polyhedron
sage: f = next(it)
sage: f
A 2-dimensional face of a 3-dimensional combinatorial polyhedron

sage: Asso = polytopes.associahedron(['A',3])
sage: C = Asso.combinatorial_polyhedron()
sage: it = C.face_iter()
sage: cython('''
....: from sage.geometry.polyhedron.combinatorial_polyhedron.face_iterator cimport *
....: def foo(FaceIterator_base it):
....:     it.next_dimension()
....:     print('a')
....:     cdef CombinatorialFace face = CombinatorialFace.__new__(CombinatorialFace)
....:     print('b')
....:     face.__init__(it)
....:     print('c')
....:     return face
....: ''')
sage: foo(it)
a
b
c
A 2-dimensional face of a 3-dimensional combinatorial polyhedron

There is definitely a problem with init and cinit as the following shoud not lead to a segmentationfault (but does and also for me):

sage: from sage.geometry.polyhedron.combinatorial_polyhedron.combinatorial_face import CombinatorialFace
sage: face = CombinatorialFace.__new__(CombinatorialFace)
sage: face.ambient_H_indices()

I don't know if this is the issue. I can try to fix this __init__ and __cinit__ things and see if this solves something.

[sagetrac-tmonteil]

comment:8

Here is a raw log, the problem are on tmonteil-lxc3, not tmonteil-lxc1, sorry for the confusion:

sagemath@tmonteil-lxc3:~/sage-9.1$ ./sage 
┌────────────────────────────────────────────────────────────────────┐
│ SageMath version 9.5.beta5, Release Date: 2021-10-28               │
│ Using Python 3.7.3. Type "help()" for help.                        │
└────────────────────────────────────────────────────────────────────┘
┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
┃ Warning: this is a prerelease version, and it may be unstable.     ┃
┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛
sage: sage: cython('''
....: ....: from sage.geometry.polyhedron.combinatorial_polyhedron.face_list_data_structure cimport *
....: ....: 
....: ....: cdef class foo:
....: ....:     cdef face_t face
....: ....:     cdef MemoryAllocator mem
....: ....:     
....: ....:     def __init__(self):
....: ....:         self.mem = MemoryAllocator()
....: ....:         face_init(self.face, 9, 14, self.mem)
....: ....:         
....: ....:     def test(self):
....: ....:         cdef face_t new_face
....: ....:         cdef mem = MemoryAllocator()
....: ....:         print('a')
....: ....:         face_init(new_face, 9, 14, mem)
....: ....:         print('b')
....: ....:         face_copy(self.face, new_face)
....: ....:         
....: ....:     def test2(self):
....: ....:         cdef face_list_t faces
....: ....:         cdef mem = MemoryAllocator()
....: ....:         print('a')
....: ....:         face_list_init(faces, 9, 9, 14, mem)
....: ....:         cdef face_t new_face
....: ....:         for i in range(9):
....: ....:             print(i)
....: ....:             new_face[0] = faces.faces[i][0]
....: ....:             print(i, 'b')
....: ....:             face_copy(self.face, new_face)
....: ....: ''')
....: sage: a = foo()
....: sage: a.test()
....: sage: a.test2()
a
b
a
0
0 b
1
1 b
2
2 b
3
3 b
4
4 b
5
5 b
6
6 b
7
7 b
8
8 b
sage: sage: sage: Asso = polytopes.associahedron(['A',3])
....: sage: it = Asso.face_generator()
....: sage: f = next(it)
....: sage: f
A 3-dimensional face of a Polyhedron in QQ^3 defined as the convex hull of 14 vertices
sage: sage: f = next(it)
....: sage: f
A -1-dimensional face of a Polyhedron in QQ^3
sage: sage: f = next(it)
....: sage: f
------------------------------------------------------------------------
Segmentation fault
sagemath@tmonteil-lxc3:~/sage-9.1$ ./sage 
┌────────────────────────────────────────────────────────────────────┐
│ SageMath version 9.5.beta5, Release Date: 2021-10-28               │
│ Using Python 3.7.3. Type "help()" for help.                        │
└────────────────────────────────────────────────────────────────────┘
┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
┃ Warning: this is a prerelease version, and it may be unstable.     ┃
┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛
sage: sage: Asso = polytopes.associahedron(['A',3])
....: sage: C = Asso.combinatorial_polyhedron()
....: sage: it = C.face_iter()
....: sage: f = next(it)
....: sage: f
------------------------------------------------------------------------
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/cysignals/signals.cpython-37m-x86_64-linux-gnu.so(+0x947b)[0x7fc34e97b47b]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/cysignals/signals.cpython-37m-x86_64-linux-gnu.so(+0xf2d8)[0x7fc34e9812d8]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/cysignals/signals.cpython-37m-x86_64-linux-gnu.so(+0xfff0)[0x7fc34e981ff0]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x12730)[0x7fc3523a9730]
/lib/x86_64-linux-gnu/libc.so.6(+0x15cb0d)[0x7fc351f48b0d]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/combinatorial_face.cpython-37m-x86_64-linux-gnu.so(+0x1305a)[0x7fc2f3a8605a]
python3[0x599551]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/face_iterator.cpython-37m-x86_64-linux-gnu.so(+0xc9ac)[0x7fc2f3a4d9ac]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/face_iterator.cpython-37m-x86_64-linux-gnu.so(+0x15948)[0x7fc2f3a56948]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/sage/geometry/polyhedron/combinatorial_polyhedron/face_iterator.cpython-37m-x86_64-linux-gnu.so(+0x1a2ef)[0x7fc2f3a5b2ef]
python3[0x556216]
python3(_PyMethodDef_RawFastCallKeywords+0x1b3)[0x5d8833]
python3(_PyEval_EvalFrameDefault+0x42c3)[0x552373]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3[0x558f25]
python3(_PyMethodDef_RawFastCallKeywords+0x1b3)[0x5d8833]
python3(_PyEval_EvalFrameDefault+0x42c3)[0x552373]
python3[0x4d37a6]
python3(_PyEval_EvalFrameDefault+0x1a75)[0x54fb25]
python3[0x4d37a6]
python3(_PyEval_EvalFrameDefault+0x1a75)[0x54fb25]
python3[0x4d37a6]
python3(_PyMethodDescr_FastCallKeywords+0x151)[0x4d76a1]
python3(_PyEval_EvalFrameDefault+0x45f8)[0x5526a8]
python3(_PyFunction_FastCallKeywords+0x18c)[0x5d91fc]
python3(_PyEval_EvalFrameDefault+0x4fc)[0x54e5ac]
python3(_PyFunction_FastCallKeywords+0x18c)[0x5d91fc]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(_PyFunction_FastCallKeywords+0x482)[0x5d94f2]
python3[0x54b1f0]
python3(_PyEval_EvalFrameDefault+0x13ae)[0x54f45e]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(_PyFunction_FastCallKeywords+0x482)[0x5d94f2]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(_PyFunction_FastCallKeywords+0x482)[0x5d94f2]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyFunction_FastCallKeywords+0x18c)[0x5d91fc]
python3(_PyEval_EvalFrameDefault+0x730)[0x54e7e0]
python3(_PyEval_EvalCodeWithName+0x252)[0x54bcc2]
python3(PyEval_EvalCode+0x23)[0x54e0a3]
python3[0x630ce2]
python3(PyRun_FileExFlags+0x97)[0x630d97]
python3(PyRun_SimpleFileExFlags+0x17f)[0x6319ff]
python3[0x65432e]
python3(_Py_UnixMain+0x2e)[0x65468e]
[1 0 1 0 0 0 0 1 0 0 0 0 0 0]
[0 1 0 1 0 1 0 0 0 0 0 0 0 0]
[0 0 1 0 1 0 0 0 0 0 0 1 0 0]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xeb)[0x7fc351e1009b]
python3(_start+0x2a)[0x5e0e8a]
------------------------------------------------------------------------
Attaching gdb to process id 1027349.
Cannot find gdb installed
GDB is not installed.
Install gdb for enhanced tracebacks.
------------------------------------------------------------------------
Unhandled SIGSEGV: A segmentation fault occurred.
This probably occurred because a *compiled* module has a bug
in it and is not properly wrapped with sig_on(), sig_off().
Python will now terminate.
------------------------------------------------------------------------
Segmentation fault
sagemath@tmonteil-lxc3:~/sage-9.1$ ./sage 
┌────────────────────────────────────────────────────────────────────┐
│ SageMath version 9.5.beta5, Release Date: 2021-10-28               │
│ Using Python 3.7.3. Type "help()" for help.                        │
└────────────────────────────────────────────────────────────────────┘
┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
┃ Warning: this is a prerelease version, and it may be unstable.     ┃
┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛
sage: sage: Asso = polytopes.associahedron(['A',3])
....: sage: C = Asso.combinatorial_polyhedron()
....: sage: it = C.face_iter()
....: sage: cython('''
....: ....: from sage.geometry.polyhedron.combinatorial_polyhedron.face_iterator cimport *
....: ....: def foo(FaceIterator_base it):
....: ....:     it.next_dimension()
....: ....:     print('a')
....: ....:     cdef CombinatorialFace face = CombinatorialFace.__new__(CombinatorialFace)
....: ....:     print('b')
....: ....:     face.__init__(it)
....: ....:     print('c')
....: ....:     return face
....: ....: ''')
....: sage: foo(it)
a
b
------------------------------------------------------------------------
Segmentation fault
sagemath@tmonteil-lxc3:~/sage-9.1$ ./sage 
┌────────────────────────────────────────────────────────────────────┐
│ SageMath version 9.5.beta5, Release Date: 2021-10-28               │
│ Using Python 3.7.3. Type "help()" for help.                        │
└────────────────────────────────────────────────────────────────────┘
┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
┃ Warning: this is a prerelease version, and it may be unstable.     ┃
┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛
sage: sage: from sage.geometry.polyhedron.combinatorial_polyhedron.combinatorial_face import CombinatorialFace
....: sage: face = CombinatorialFace.__new__(CombinatorialFace)
....: sage: face.ambient_H_indices()
------------------------------------------------------------------------
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/cysignals/signals.cpython-37m-x86_64-linux-gnu.so(+0x947b)[0x7f644a84747b]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/cysignals/signals.cpython-37m-x86_64-linux-gnu.so(+0xf2d8)[0x7f644a84d2d8]
/home/sagemath/sage-9.1/local/lib/python3.7/site-packages/cysignals/signals.cpython-37m-x86_64-linux-gnu.so(+0xfff0)[0x7f644a84dff0]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x12730)[0x7f644e275730]
------------------------------------------------------------------------
Attaching gdb to process id 1027750.
Cannot find gdb installed
GDB is not installed.
Install gdb for enhanced tracebacks.
------------------------------------------------------------------------
Unhandled SIGSEGV: A segmentation fault occurred.
This probably occurred because a *compiled* module has a bug
in it and is not properly wrapped with sig_on(), sig_off().
Python will now terminate.
------------------------------------------------------------------------
Segmentation fault

[sagetrac-tmonteil]

comment:9

I edited comment:2 to fix the typo between lxc1 and lxc3, the relative tickets are correct.

[kliem]

comment:10

Thanks for all your help.

I will make a branch, where I put things in __cinit__ that belong there. I hope that helps.

In the meantime can you yet run the following:

sage: cython('''
....: from sage.geometry.polyhedron.combinatorial_polyhedron.face_list_data_structure cimport *
....: 
....: cdef class foo:
....:     cdef face_t face
....:     cdef MemoryAllocator mem
....:     
....:     def __init__(self):
....:         self.mem = MemoryAllocator()
....:         face_init(self.face, 9, 14, self.mem)
....:         
....:     def test(self):
....:         cdef face_t new_face
....:         cdef mem = MemoryAllocator()
....:         print('a')
....:         face_init(new_face, 9, 14, mem)
....:         print('b')
....:         face_copy(self.face, new_face)
....:         
....:     def test2(self):
....:         cdef face_list_t faces
....:         cdef mem = MemoryAllocator()
....:         print('a')
....:         face_list_init(faces, 9, 9, 14, mem)
....:         cdef face_t new_face
....:         for i in range(9):
....:             print(i)
....:             new_face[0] = faces.faces[i][0]
....:             print(i, 'b')
....:             face_copy(self.face, new_face)
....: ''')
sage: a = foo()
sage: a.test()
sage: a.test2()
sage: a = foo.__new__(foo)
sage: a.__init__()
sage: a.test()
sage: a.test2()

It's different from the above, as it now uses incorrectly __init__ instead of __cinit__ as done throughout the module combinatorial_polyhedron.