py-pytorch: Symbol not found: __ZdlPvSt11align_val_t

[chrstphrchvz (Christopher Chavez)]

On macOS 10.12, pytorch can't be imported, as currently observed in the build logs for pyXX-torchvision:

Traceback (most recent call last):
  File "setup.py", line 13, in <module>
    import torch
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/torch/__init__.py", line 189, in <module>
    from torch._C import *
ImportError: dlopen(/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/torch/_C.cpython-36m-darwin.so, 2): Symbol not found: __ZdlPvSt11align_val_t
  Referenced from: /opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/torch/lib/libtorch_python.dylib
  Expected in: /usr/lib/libc++.1.dylib
 in /opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/torch/lib/libtorch_python.dylib

From searching online, this has to do with std::uncaught_exceptions() not being found in libc++.

[mascguy (Christopher Nielsen)]

While he's not listed in the portfile, my understanding is that cjones051073 is the py-pytorch maintainer. Go ahead and assign this ticket to him.

[mascguy (Christopher Nielsen)]

LLVM folks, is this a limitation of the host libc++, or... ?

[mascguy (Christopher Nielsen)]

Can anyone speak to this issue? Is it a limitation of the host libc++, an unpatched issue in the MacPorts-provided tool chain, ...?

[mascguy (Christopher Nielsen)]

KenC/anyone, can you speak to whether this is a host libcc++ issue, and/or something that needs to be corrected in the MacPorts-provided toolchain...?

[kencu (Ken)]

looks like the host libc++ doesn't have the desired symbol.

options would be to either not use that symbol (build configuration, source patch) or try using a newer libc++ like macports-libcxx

[cjones051073 (Chris Jones)]

Sorry, missed this until now...

Another option is to use the standard 'emulation' of std::uncaught_exceptions() with ( std::uncaught_exception() ? 1 : 0 )

Also it might be an option to add this to legacy support....

[cjones051073 (Chris Jones)]

Hmmm.. cannot reproduce on my 10.12 VM (using python 3.9 as 3.6 support has since been removed)

Also seems like last build attempt on 10.12 was OK

​https://ports.macports.org/port/py39-torchvision/builds

[mascguy (Christopher Nielsen)]

Replying to cjones051073:

Hmmm.. cannot reproduce on my 10.12 VM (using python 3.9 as 3.6 support has since been removed)

Also seems like last build attempt on 10.12 was OK

​https://ports.macports.org/port/py39-torchvision/builds

That's good news!

@ChristopherChavez, are you still encountering this issue with 3.7, 3.8, or 3.9?

[chrstphrchvz (Christopher Chavez)]

I reported this on behalf of builders. I personally do not use this port nor macOS 10.12.