WIP: {devel}[foss/2020a] PyTorch v1.4.0 w/ Python 3.8.2

[branfosj]

(created using eb --new-pr)

Requires:

• PyYAML ({lib}[GCCcore/9.3.0] PyYAML v5.3, libyaml v0.2.2 w/ Python 2.7.17 + 3.8.2 #10138)
• Pillow ({vis}[GCCcore/9.3.0] Pillow v7.0.0 w/ Python 3.8.2 #10137)

This is very much a WIP, since it:

• fails to build on cascadelake
• fails in the tests on everything else

I've generated test reports to allow me to debug.

[branfosj]

Test report by @branfosj
FAILED
Build succeeded for 0 out of 1 (1 easyconfigs in this PR)
bear-pg0211u03a.bear.cluster - Linux centos linux 7.7.1908, Intel(R) Xeon(R) Gold 6248 CPU @ 2.50GHz, Python 2.7.5
See https://gist.github.com/be7f8f79a5e6c2bd113b86c2f6577f3e for a full test report.

[branfosj]

Test report by @branfosj
FAILED
Build succeeded for 0 out of 1 (1 easyconfigs in this PR)
bear-pg0306u03a.bear.cluster - Linux RHEL 7.6, 8335-GTX, Python 2.7.5
See https://gist.github.com/c0eb43e94e79486bfb4e87323426380f for a full test report.

[zao]

Test report by @zao
FAILED
Build succeeded for 12 out of 13 (1 easyconfigs in this PR)
freja - Linux ubuntu 18.04, Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz, Python 2.7.17
See https://gist.github.com/eb71991086c3caef685472a53e1c6310 for a full test report.

[branfosj]

Test report by @branfosj
FAILED
Build succeeded for 0 out of 1 (1 easyconfigs in this PR)
bear-pg0211u03a.bear.cluster - Linux centos linux 7.7.1908, Intel(R) Xeon(R) Gold 6248 CPU @ 2.50GHz, Python 2.7.5
See https://gist.github.com/be7f8f79a5e6c2bd113b86c2f6577f3e for a full test report.

The CascadeLake build failure is in FBGEMM. The build does not fail if we set toolchainopts = {'optarch': False}, so we are back in the -march=native causing issues.

(Note that this gets the build part to complete on CascadeLake - we fail in the tests in the same place that all the others were failing.)

[branfosj]

PyTorch 1.5 has been released (https://github.com/pytorch/pytorch/releases/tag/v1.5.0). I'll close this off as we should go with that in the 2020a branch.