Hi,
Regarding ATEN_CPU_CAPABILITY:
steph@steph-desktop:~$ export ATEN_CPU_CAPABILITY=default
steph@steph-desktop:~$ echo $ATEN_CPU_CAPABILITY
default
steph@steph-desktop:~$ python3.7
Python 3.7.5 (default, Nov  7 2019, 10:50:52)
[GCC 8.3.0] on linux
Type “help”, “copyright”, “credits” or “license” for more information.



import torch
torch.version
‘1.6.0’




a=torch.randn(1,3,5)
a.max(1)
Illegal instruction (core dumped)



Regarding gdb output:
For python3.7.5 and torch==1.6.0 the gdb output is:
steph@steph-desktop:~$ gdb python3.7 -ex “set args -c ‘import torch;print(torch.rand(1,2,5).max(1))’” -ex “run” -ex “bt”
GNU gdb (Ubuntu 8.1-0ubuntu3.2) 8.1.0.20180409-git
Copyright © 2018 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later …
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type “show copying”
and “show warranty” for details.
This GDB was configured as “x86_64-linux-gnu”.
Type “show configuration” for configuration details.
For bug reporting instructions, please see:
.
Find the GDB manual and other documentation resources online at:
.
For help, type "help".
Type "apropos word" to search for commands related to "word"...
Registered pretty printers for UE4 classes
Reading symbols from python3.7...(no debugging symbols found)...done.
Starting program: /usr/bin/python3.7 -c 'import torch;print(torch.rand(1,2,5).max(1))'
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7fffa5778700 (LWP 3552)]
[New Thread 0x7fffa4f77700 (LWP 3553)]
[New Thread 0x7fffa2776700 (LWP 3554)]
[New Thread 0x7fff9df75700 (LWP 3555)]
[New Thread 0x7fff9b774700 (LWP 3556)]
Thread 1 “python3.7” received signal SIGILL, Illegal instruction.
0x00007fffe4c04409 in at::TensorIteratorConfig::declare_static_shape(c10::ArrayRef, long) ()
from /home/steph/.local/lib/python3.7/site-packages/torch/lib/libtorch_cpu.so
#0  0x00007fffe4c04409 in at::TensorIteratorConfig::declare_static_shape(c10::ArrayRef, long) ()
from /home/steph/.local/lib/python3.7/site-packages/torch/lib/libtorch_cpu.so
#1  0x00007fffe54e66f7 in at::native::(anonymous namespace)::max_kernel_impl ()
from /home/steph/.local/lib/python3.7/site-packages/torch/lib/libtorch_cpu.so
#2  0x00007fffe449d83e in void at::native::DispatchStub<void ()(at::Tensor&, at::Tensor&, at::Tensor const&, long, bool), at::native::max_stub>::operator()<at::Tensor&, at::Tensor&, at::Tensor const&, long&, bool&>(c10::DeviceType, at::Tensor&, at::Tensor&, at::Tensor const&, long&, bool&) () from /home/steph/.local/lib/python3.7/site-packages/torch/lib/libtorch_cpu.so
#3  0x00007fffe4499bd2 in at::native::max_out(at::Tensor&, at::Tensor&, at::Tensor const&, long, bool) ()
from /home/steph/.local/lib/python3.7/site-packages/torch/lib/libtorch_cpu.so
#4  0x00007fffe449a77f in at::native::max(at::Tensor const&, long, bool) ()
from /home/steph/.local/lib/python3.7/site-packages/torch/lib/libtorch_cpu.so
#5  0x00007fffe48d3047 in at::TypeDefault::max_dim(at::Tensor const&, long, bool) ()
from /home/steph/.local/lib/python3.7/site-packages/torch/lib/libtorch_cpu.so
#6  0x00007fffe4751544 in c10::impl::wrap_kernel_functor_unboxed_<c10::impl::detail::WrapFunctionIntoRuntimeFunctor_<std::tuple<at::Tensor, at::Tensor> ()(at::Tensor const&, long, bool), std::tuple<at::Tensor, at::Tensor>, c10::guts::typelist::typelist<at::Tensor const&, long, bool> >, std::tuple<at::Tensor, at::Tensor> (at::Tensor const&, long, bool)>::call(c10::OperatorKernel*, at::Tensor const&, long, bool) () from /home/steph/.local/lib/python3.7/site-packages/torch/lib/libtorch_cpu.so
#7  0x00007fffe47ebf54 in at::max(at::Tensor const&, long, bool) ()
from /home/steph/.local/lib/python3.7/site-packages/torch/lib/libtorch_cpu.so
#8  0x00007fffe648b9e2 in torch::autograd::VariableType::max_dim(at::Tensor const&, long, bool) ()
from /home/steph/.local/lib/python3.7/site-packages/torch/lib/libtorch_cpu.so
#9  0x00007fffe4751544 in c10::impl::wrap_kernel_functor_unboxed_<c10::impl::detail::WrapFunctionIntoRuntimeFunctor_<std::tup—Type  to continue, or q  to quit—
le<at::Tensor, at::Tensor> ()(at::Tensor const&, long, bool), std::tuple<at::Tensor, at::Tensor>, c10::guts::typelist::typelist<at::Tensor const&, long, bool> >, std::tuple<at::Tensor, at::Tensor> (at::Tensor const&, long, bool)>::call(c10::OperatorKernel, at::Tensor const&, long, bool) () from /home/steph/.local/lib/python3.7/site-packages/torch/lib/libtorch_cpu.so
#10 0x00007fffe4974944 in at::Tensor::max(long, bool) const ()
from /home/steph/.local/lib/python3.7/site-packages/torch/lib/libtorch_cpu.so
#11 0x00007ffff3de9d33 in torch::autograd::THPVariable_max(_object*, _object*, _object*) ()
from /home/steph/.local/lib/python3.7/site-packages/torch/lib/libtorch_python.so
#12 0x00000000004d6194 in _PyMethodDescr_FastCallKeywords ()
#13 0x0000000000551d89 in _PyEval_EvalFrameDefault ()
#14 0x000000000054b302 in _PyEval_EvalCodeWithName ()
#15 0x0000000000530aef in PyRun_StringFlags ()
#16 0x000000000063138d in PyRun_SimpleStringFlags ()
#17 0x000000000065473d in ?? ()
#18 0x000000000065486e in _Py_UnixMain ()
#19 0x00007ffff7a05b97 in __libc_start_main (main=0x4b84d0 , argc=3, argv=0x7fffffffdba8, init=,
fini=, rtld_fini=, stack_end=0x7fffffffdb98) at …/csu/libc-start.c:310
#20 0x00000000005df80a in _start ()
(gdb) quit
A debugging session is active.
Inferior 1 [process 3542] will be killed.

Quit anyway? (y or n) y
steph@steph-desktop:~$
While with python3.7.5 and torch==1.5.0 installed, the gdb output is:
steph@steph-desktop:~$ gdb python3.7 -ex “set args -c ‘import torch;print(torch.rand(1,2,5).max(1))’” -ex “run” -ex “bt”
GNU gdb (Ubuntu 8.1-0ubuntu3.2) 8.1.0.20180409-git
Copyright © 2018 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later (link)
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type “show copying”
and “show warranty” for details.
This GDB was configured as “x86_64-linux-gnu”.
Type “show configuration” for configuration details.
For bug reporting instructions, please see:
(link).
Find the GDB manual and other documentation resources online at: (link)
For help, type “help”.
Type “apropos word” to search for commands related to “word”…
Registered pretty printers for UE4 classes
Reading symbols from python3.7…(no debugging symbols found)…done.
Starting program: /usr/bin/python3.7 -c ‘import torch;print(torch.rand(1,2,5).max(1))’
[Thread debugging using libthread_db enabled]
Using host libthread_db library “/lib/x86_64-linux-gnu/libthread_db.so.1”.
[New Thread 0x7fffa59f8700 (LWP 3197)]
[New Thread 0x7fffa51f7700 (LWP 3198)]
[New Thread 0x7fffa09f6700 (LWP 3199)]
[New Thread 0x7fff9e1f5700 (LWP 3200)]
[New Thread 0x7fff9b9f4700 (LWP 3201)]
[New Thread 0x7fff92dcd700 (LWP 3203)]
[New Thread 0x7fff925cc700 (LWP 3204)]
[New Thread 0x7fff91dcb700 (LWP 3205)]
[New Thread 0x7fff915ca700 (LWP 3206)]
[New Thread 0x7fff90dc9700 (LWP 3207)]
torch.return_types.max(
values=tensor([[0.3803, 0.9634, 0.5299, 0.9652, 0.6461]]),
indices=tensor([[1, 1, 0, 0, 0]]))
[Thread 0x7fff9b9f4700 (LWP 3201) exited]
[Thread 0x7fff90dc9700 (LWP 3207) exited]
[Thread 0x7fff915ca700 (LWP 3206) exited]
[Thread 0x7fff91dcb700 (LWP 3205) exited]
[Thread 0x7fff925cc700 (LWP 3204) exited]
[Thread 0x7fff92dcd700 (LWP 3203) exited]
[Thread 0x7fff9e1f5700 (LWP 3200) exited]
[Thread 0x7fffa09f6700 (LWP 3199) exited]javascript:;
[Thread 0x7fffa51f7700 (LWP 3198) exited]
[Thread 0x7fffa59f8700 (LWP 3197) exited]
[Inferior 1 (process 3187) exited normally]
No stack.
(gdb) quit