Import tweedledum failing on MacOS

[Arihant-Joshi]

Describe the bug

Whenever I'm trying to import something from the tweedledum module, it throws an ImportError. e.g. from tweedledum.classical import simulate or import tweedledum fail with the following stacktrace-

>>> from tweedledum.classical import simulate
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/arihant/opt/anaconda3/envs/qiskit/lib/python3.8/site-packages/tweedledum/__init__.py", line 5, in <module>
    from ._tweedledum import *
ImportError: dlopen(/Users/arihant/opt/anaconda3/envs/qiskit/lib/python3.8/site-packages/tweedledum/_tweedledum.cpython-38-darwin.so, 2): Symbol not found: _aligned_alloc
  Referenced from: /Users/arihant/opt/anaconda3/envs/qiskit/lib/python3.8/site-packages/tweedledum/_tweedledum.cpython-38-darwin.so
  Expected in: /usr/lib/libSystem.B.dylib
 in /Users/arihant/opt/anaconda3/envs/qiskit/lib/python3.8/site-packages/tweedledum/_tweedledum.cpython-38-darwin.so

Expected behavior

The libraries get imported.

Information

• tweedledum version: 1.1.0
• Python version: 3.8.10
• Operating system: MacOS Mojave Version 10.14.6 (18G8022)

Additional context

I'm running it from a conda environment - conda 4.10.1.(which I have tried re-installing to try fixing this)

EDIT: The same works on my windows machine, so might be a MacOS specific issue.

[eileen-kuehn]

Same here, MacOS 10.14.5, Apple LLVM version 10.0.1 (clang-1001.0.46.4). Tested with pip install tweedledum for Python 3.8.11 in a clean venv setup and Python 3.7.9. I also failed to install tweedledum==1.1.0 via pip install tweedledum==1.1.0 --no-binary tweedledum. Installation of version 1.0.0 seems to work fine.

[epelofske65537]

pip install tweedledum==1.0.0 fixed the problem for me

[boschmitt]

Seems like the problem is that I'm building on MacOS 10.15 (Catalina), and using the MacOS 10.9 SDK while building. Furthermore, I'm using GCC 10 while linking against libstdc++, which Apples seems to discourage in favor of libc++.

There might be some problem with my CI build script, I will try to fix it. Unfortunately, I don't have means to test a possible solution on my side.

[mtreinish]

@boschmitt one way we can test this is to have the ci job on the fix PR and upload the wheel to artifacts and then ask @eileen-kuehn or @Arihant-Joshi (or any other users experiencing the issue) to test that wheel file locally. That's what I normally do in these situations where there are platform specific issues and I don't have access to the platform.

[boschmitt]

@boschmitt one way we can test this is to have the ci job on the fix PR and upload the wheel to artifacts and then ask @eileen-kuehn or @Arihant-Joshi (or any other users experiencing the issue) to test that wheel file locally. That's what I normally do in these situations where there are platform specific issues and I don't have access to the platform.

Thanks @mtreinish! I was planning on trying fixes on tweedledum-dev, having them test it, and then do a patch to the main package. However, now I realized that I actually have access to some old mac computers. I just didn't had the time to get them to debug this problem. On the CI it's passing all tests, which I believe might be because it have homebrew gcc installed.

[eileen-kuehn]

@boschmitt, I am happy to do some tests for you as soon as you let me know :)

[cacosomoza]

Hi all, I've been facing the same issue on High Sierra 10.13.6 and conda 4.10.3. Unfortunately downgrading to tweedledum 1.0.0 didn't do the trick for me:

ImportError: dlopen(/Users/Caco/anaconda3/envs/NEW_QISKIT/lib/python3.8/site-packages/tweedledum/_tweedledum.cpython-38-darwin.so, 2): Symbol not found: _aligned_alloc Referenced from: /Users/Caco/anaconda3/envs/NEW_QISKIT/lib/python3.8/site-packages/tweedledum/_tweedledum.cpython-38-darwin.so Expected in: /usr/lib/libSystem.B.dylib in /Users/Caco/anaconda3/envs/NEW_QISKIT/lib/python3.8/site-packages/tweedledum/_tweedledum.cpython-38-darwin.so

[boschmitt]

@boschmitt, I am happy to do some tests for you as soon as you let me know :)

Hi @eileen-kuehn, Thanks. Could you try installing tweedledum-dev and see if it works. (You will need to uninstall tweedledum or install it in a new env)

[eileen-kuehn]

@boschmitt, the tweedledum-dev package is working great for me 👍 I cannot see any issues anymore.

[boschmitt]

After much thought, I decided to drop support for macOS High Sierra (10.13) and macOS Mojave (10.14). From now on, I will support both systems on a best-effort basis. Meaning that some I won't build wheels for all releases. The reason is simple: I was not able to successfully build these wheels using a GitHub workflow.

The workaround is to install tweedledum directly from source:

CC=gcc-10 CXX=g++-10 CXXFLAGS="-static-libgcc -static-libstdc++" pip install tweedledum --no-binary :all:

Note that this requires a gcc that has been build for the specific macOS you are using. (This should work with any version with C++17 support, but I only tested with gcc10 and gcc11.) Indeed, the CI box has various gcc versions installed, but they were all built for macOS 10.15. Currently, even if I set the deployment target to be 10.9 (or 10.13) and statically link against standard libraries, the compiler/linker still assumes that the aligned_alloc function will be provided by some other library.

[eileen-kuehn]

The workaround is to install tweedledum directly from source:

CC=gcc-10 CXX=g++-10 CXXFLAGS="-static-libgcc -static-libstdc++" pip install tweedledum --no-binary :all:

In my case, the workaround is perfectly fine 👍 and I am happy to install tweedledum like this. Thanks a lot for your efforts!