Dear all,
I'm struggling to understand strange segfaults coming from ECL(+Maxima) on FreeBSD embedded into Python; they typically look as follows:
Got signal before environment was installed on our thread [2: No such file or directory]
;;; ECL C Backtrace ;;; 0 ecl_internal_error (0x87d790765) ;;; 1 init_unixint (0x87d7b6bd0) ;;; 2 init_unixint (0x87d7b6972) ;;; 3 pthread_sigmask (0x80103779d) ;;; 4 pthread_getspecific (0x801036d6f) ;;; 5 unknown (0x7ffffffff193) ;;; 6 GC_push_all_stacks (0x87db1ea2c) ;;; 7 GC_mark_some (0x87db12eec) ;;; 8 GC_stopped_mark (0x87db09baa) ;;; 9 GC_try_to_collect_inner (0x87db09a75) ;;; 10 GC_init (0x87db16f4f) ;;; 11 init_alloc (0x87d7caa59) ;;; 12 cl_boot (0x87d694a5b) ;;; 13 initecl (0x87d218340) ;;; 14 initecl (0x87d20a43f) ;;; 15 initecl (0x87d207e28) ;;; 16 _PyImport_LoadDynamicModule (0x800b3ed1c) ;;; 17 PyImport_AppendInittab (0x800b3d71f) ;;; 18 PyImport_AppendInittab (0x800b3d1a8) ;;; 19 PyImport_ImportModuleLevel (0x800b3c2ce) ;;; 20 _PyBuiltin_Init (0x800b162d7) ;;; 21 PyObject_Call (0x800a7d3e3) ;;; 22 PyEval_EvalFrameEx (0x800b2121c) ;;; 23 PyEval_EvalCodeEx (0x800b1b5d4) ;;; 24 PyEval_EvalCode (0x800b1ad96) ;;; 25 PyImport_ExecCodeModuleEx (0x800b3ad11) ;;; 26 PyImport_AppendInittab (0x800b3ddb8) ;;; 27 PyImport_AppendInittab (0x800b3d71f) ;;; 28 PyImport_AppendInittab (0x800b3d1a8) ;;; 29 PyImport_ImportModuleLevel (0x800b3c2ce) ;;; 30 _PyBuiltin_Init (0x800b162d7) ;;; 31 PyEval_EvalFrameEx (0x800b22dd1) Segmentation fault (core dumped)
It looks as if ECL (version 16.1.2) is being called before an initialisation is complete, but it it possible to say more without a debugger?
More details: is is on FreeBSD 11.0, clang 3.8.0, GC version 7.6.0 with libatomic_ops version 7.4.6. And only reproducible on FreeBSD.
ECL is built with --disable-threads; GC is built with or without threads---result is still the same. (so it's unclear to me where pthread_* calls in the trace come from).
Thanks, Dima
PS. the segfault is at the bottom of https://trac.sagemath.org/ticket/22679#comment:87