Installation of earlier versions of Python (prior to 3.8) fails on Mac with M1 Chip (ARM based Apple Silicon)

Question:

I have Macbook with Apple M1 Chip in which I have to use Python 3.6.5 for my project. It comes with Python 2.7.16 and 3.8.2 preinstalled. I used brew to install Python which by default installed 3.9.1.

So, I tried this homebrew formula to install 3.6.5, but got following error:

checking for pthread_t... yes
checking size of pthread_t... 8
configure: error: Unexpected output of 'arch' on OSX

Do not report this issue to Homebrew/brew or Homebrew/core!

I tried pyenv install 3.6.5 , but it fails with similar error as above. Method explained here by ePi272314 to install python with git commit fails because it is no longer supported in homebrew.

When I try running Terminal with Rosetta 2 and install python 3.6.5, using above methods, I get the following, or some other compilation error:

Error: Cannot install in Homebrew under Rosetta 2 in ARM default prefix (/opt/homebrew)!

Finally, I downlaoded dmg file of Python 3.6.5 and installed it. It installed fine and it is visible as a python3 installation at /usr/local/bin/python3 but it cannot run.

kxxxr@Kxxxns-MBP bin % where python3
/opt/homebrew/bin/python3
/Library/Frameworks/Python.framework/Versions/3.6/bin/python3
/opt/homebrew/bin/python3
/usr/local/bin/python3
/usr/bin/python3
kxxxr@Kxxxns-MBP bin % /opt/homebrew/bin/python3 --version
Python 3.9.1
kxxxr@Kxxxns-MBP bin % /usr/local/bin/python3 --version
zsh: killed     /usr/local/bin/python3 --version
kxxxr@Kxxxns-MBP bin % 

Idle installed by Python dmg file cannot run either (I have admin rights).

Lastly came across this python bug report, which says bug is being fixed for Python 3.8, 3.9 and 3.10. Clearly, it looks like older version will not be supported on M1 chips officially.

My question is:

  1. Is there other way to work with Python 3.6.5 on Mac M1? Am I missing anything?
  2. If not, then please mention that. I will accept that as answer.

Thanks in advance.

Asked By: Kundan Kumar

||

Answers:

Using answer of @Charles Duffy you can make older versions run on M1s.
However Python versions before 3.8 will NOT be officially supported on M1 because they were not in bug-fix phase when M1 chips were released. It is stated clearly here as:

">Are there plans to backport PR 22855 to any branches older than 3.9?

The plan is to also support 3.8 on Big Sur and Apple Silicon as 3.8 is still in bugfix mode. There are no plans to backport support to 3.7 and 3.6 which are in the security-fix-only phase of their release cycles."

in this python bug tracker.

So I don’t think there is any way to get them working on M1 unless someone tweaks python on their own.

Answered By: Kundan Kumar

Nix installed under Rosetta 2 will do the trick. I didn’t even have it installed before running the below — note the message showing Nix downloading Python 3.6 when I requested it.

# yes, this really is a M1 Mac
charles@macbook-pro ~ % uname -a
Darwin macbook-pro.lan 20.2.0 Darwin Kernel Version 20.2.0: Wed Dec  2 20:40:21 PST 2020; root:xnu-7195.60.75~1/RELEASE_ARM64_T8101 x86_64 i386 MacBookPro17,1 Darwin
charles@macbook-pro ~ % arch
arm64

# ...however, Rosetta was used to install an x86_64 Nix build
charles@macbook-pro ~ % file "$(realpath "$(command -v nix)")"
/nix/store/104sp9zrhmh3jycj32jcyl3f13mysdki-nix-2.3.9/bin/nix: Mach-O 64-bit executable x86_64

# ...and that x86_64 Nix build can install and run an x86_64 Python 3.6
charles@macbook-pro ~ % nix run nixpkgs.python36 -c python
[1 copied (53.7 MiB), 9.3 MiB DL]
Python 3.6.12 (default, Dec 18 2020, 15:32:50) 
[GCC 4.2.1 Compatible Clang 7.1.0 (tags/RELEASE_710/final)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> 

The above (for reproducibility purposes) was collected with nixpkgs referring to the channel https://nixos.org/channels/nixpkgs-20.09-darwin, and specifically to the instance sn5ycj9wkbdmyinvqyg9rn42sw71wqad-nixpkgs-20.09pre245572.f18fbc33930.

Answered By: Charles Duffy

Python 3.6 is not support on M1 might due to the fact that 3.6 will reach End Of Line (EOL) at the end of this year (2021).

I would suggest you to try at least Python 3.7 or higher on M1. Using pyenv, I’ve succeed install Python 3.7.10, 3.8.6 and 3.9.4 natively on macOS 11 (Apple Silicon). This article would help you though the process, if you’re still looking for answer: https://squademy.medium.com/install-python-on-macos-11-m1-apple-silicon-using-pyenv-12e0729427a9

Answered By: Eugene

Although it’s EOL, you can install the final version 3.6.15 on a Mac M1 using pyenv.

Answered By: RonanOD

I was able to install 3.8 from source:

./configure --enable-framework=/Users/MyUName/lib/Frameworks
make && make install

I tried 3.7 and it died during make:

cd Mac && /Applications/Xcode.app/Contents/Developer/usr/bin/make pythonw
gcc  -DPYTHONFRAMEWORK='"Python"' -o pythonw 
        ./Tools/pythonw.c -I.. -I./../Include 
        ../Python.framework/Versions/3.7/Python
./Tools/pythonw.c:125:9: error: "Unknown CPU"
#       error "Unknown CPU"
        ^

I tried 3.6 and it died during config:

checking for g++... no
configure:

  By default, distutils will build C++ extension modules with "g++".
  If this is not intended, then set CXX on the configure command line.

so I tried adding CXX=$(xcode-select -p)/usr/bin/g+ and it didn’t get much further:

checking for the platform triplet based on compiler characteristics... darwin
configure: error: internal configure error for the platform triplet, please file a bug report

Conda doesn’t even support 3.6 and 3.7 for M1.

Answered By: Zach Young

I am a bit late compared to the other answers, but I was struggling with this as well. I found a different solution.

I wanted to use conda to make a python3.6 environment, but this kept failing on my Mac with a M1 chip

conda create --name myenv python=3.6
Collecting package metadata (current_repodata.json): done
Solving environment: failed with repodata from current_repodata.json, will retry with next repodata source.
Collecting package metadata (repodata.json): done
Solving environment: failed
PackagesNotFoundError: The following packages are not available from current channels:
 - python=3.6

best I could do was python 3.8, even when using --channel conda-forge.

The solution was downloading a different version of conda miniconda3. instead of selecting the "Miniconda3 macOS Apple M1 64-bit pkg" I chose the "Miniconda3 macOS Intel x86 64-bit pkg" (intel version). Now creating a python 3.6 conda environment runs smoothly. This way you can still run old code in the conda environment, without messing with the mac python version.

Hope this helps others as well, as the above solutions did not seem to work.

Answered By: Fini