Archspec not implemented for Windows

[intentionally-left-nil]

Troubleshooting docs

• My problem is not solved in the Troubleshooting docs

Anaconda default channels

• I do NOT use the Anaconda default channels (pkgs/* etc.)

How did you install Mamba?

Micromamba

Search tried in issue tracker

archspec, x86_64, microarch

Latest version of Mamba

• My problem is not solved with the latest version

Tried in Conda?

I do not have this problem with Conda, just with Mamba

Describe your issue

micromamba info -v always returns __archspec=1=x86_64 on Windows, x64 machines. The net result is that windows users will never get optimized packages without manually overriding the archspec

This is due to get_archspec_x86_64 only working for GCC and clang builds. However, the release micromamba binary from conda-forge uses [MSVC] (Microsoft Visual C compiler)

which causes this ifdef to evaluate to false: #if (defined(__GNUC__) || defined(__clang__)) && __x86_64__
It's not as simple as just changing the ifdef, because __builtin_cpu_supports is gcc specific. Instead, on MSVC, you'll need to use __cpuid instead for that compiler

mamba info / micromamba info

(Sensitive paths stripped)


       libmamba version : 2.0.5
     micromamba version : 2.0.5
           curl version : libcurl/8.8.0-DEV Schannel zlib/1.3.1
     libarchive version : libarchive 3.7.2 zlib/1.3.1 liblzma/5.6.2 bz2lib/1.0.8 liblz4/1.9.4 libzstd/1.5.6
   
            environment : base
    
       virtual packages : __win=10.0.22631=0
                          __archspec=1=x86_64
                          __cuda=12.7=0
               channels : https://conda.anaconda.org/conda-forge/noarch
                          https://conda.anaconda.org/conda-forge/win-64
               platform : win-64

Logs

environment.yml

~/.condarc