Python 3.13.15 linux-64 build hf47f18c_102_cp313 has malformed -partition=none sysconfig flag

[tgoldina]

Solution to issue cannot be found in the documentation.

• I checked the documentation.

Issue

Please notice -partition=none below:

# Name                     Version          Build               Channel
libpython                  3.13.15          hdc7f604_102_cp313  conda-forge
python                     3.13.15          hf47f18c_102_cp313  conda-forge
python_abi                 3.13             9_cp313             conda-forge
CFLAGS: -fno-strict-overflow -Wsign-compare -DNDEBUG -O2 -Wall    -fPIC   -O2   -fno-merge-constants -isystem /usr/share/miniconda/envs/test/include -fdebug-prefix-map=/home/conda/feedstock_root/build_artifacts/python-split_1788361500653/work=/usr/local/src/conda/python-split-3.13.15  -fuse-linker-plugin -ffat-lto-objects -partition=none     -fPIC   -O2   -fno-merge-constants -isystem /usr/share/miniconda/envs/test/include -fdebug-prefix-map=/home/conda/feedstock_root/build_artifacts/python-split_1788361500653/work=/usr/local/src/conda/python-split-3.13.15  -fuse-linker-plugin -ffat-lto-objects -partition=none 
PY_CFLAGS: -fno-strict-overflow -Wsign-compare -DNDEBUG -O2 -Wall    -fPIC   -O2   -fno-merge-constants -isystem /usr/share/miniconda/envs/test/include -fdebug-prefix-map=/home/conda/feedstock_root/build_artifacts/python-split_1788361500653/work=/usr/local/src/conda/python-split-3.13.15  -fuse-linker-plugin -ffat-lto-objects -partition=none     -fPIC   -O2   -fno-merge-constants -isystem /usr/share/miniconda/envs/test/include -fdebug-prefix-map=/home/conda/feedstock_root/build_artifacts/python-split_1788361500653/work=/usr/local/src/conda/python-split-3.13.15  -fuse-linker-plugin -ffat-lto-objects -partition=none 
PY_CFLAGS_NODIST: -D_Py_TIER2=3 -D_Py_JIT -fno-semantic-interposition  -fuse-linker-plugin -ffat-lto-objects -partition=none -g -std=c11 -Wextra -Wno-unused-parameter -Wno-missing-field-initializers -Wstrict-prototypes -Werror=implicit-function-declaration -fvisibility=hidden   -I/home/conda/feedstock_root/build_artifacts/python-split_1788361500653/work/Include/internal -I/home/conda/feedstock_root/build_artifacts/python-split_1788361500653/work/Include/internal/mimalloc

To reproduce:

conda create -n py313-test \
    -c conda-forge \
    "python=3.13.15=hf47f18c_102_cp313"

conda activate py313-test
conda list python

python - <<'PY'
import sysconfig
for key in ("CFLAGS", "PY_CFLAGS", "PY_CFLAGS_NODIST"):
    print(key, "=", sysconfig.get_config_var(key))
PY

This is regression bug that showed up this morning.

Installed packages

# packages in environment at /home/tatianag/miniforge3/envs/py313-test:
#
# Name                    Version                   Build  Channel
_openmp_mutex             4.5                      20_gnu    conda-forge
bzip2                     1.0.8               hda65f42_10    conda-forge
ca-certificates           2026.7.22            hbd8a1cb_0    conda-forge
icu                       78.3            py310h44b86e0_2    conda-forge
ld_impl_linux-64          2.46.1          default_hbd61a6d_102    conda-forge
libexpat                  2.8.1                hecca717_1    conda-forge
libffi                    3.7.0                h81df57d_1    conda-forge
libgcc                    16.2.0               ha9f2e26_4    conda-forge
libgomp                   16.2.0               he0feb66_4    conda-forge
liblzma                   5.8.3                hb03c661_1    conda-forge
libmpdec                  4.0.0                hb03c661_2    conda-forge
libpython                 3.13.15         hdc7f604_102_cp313    conda-forge
libsqlite                 3.53.4               h13e7031_1    conda-forge
libstdcxx                 16.2.0               h934c35e_4    conda-forge
libuuid                   2.42.3               hcfc3c73_0    conda-forge
libzlib                   1.3.2                h25fd6f3_3    conda-forge
ncurses                   6.6                  hdb14827_1    conda-forge
openssl                   3.6.4                h781a0a9_0    conda-forge
pip                       26.2.1             pyh145f28c_0    conda-forge
python                    3.13.15         hf47f18c_102_cp313    conda-forge
python_abi                3.13                    9_cp313    conda-forge
readline                  8.3                  hd6e31c0_1    conda-forge
tk                        8.6.13          noxft_h1df4ec4_4    conda-forge
tzdata                    2026c                h151e31d_0    conda-forge
zstd                      1.5.7                hb78ec9c_7    conda-forge

Environment info

active environment : py313-test
    active env location : /home/username/miniforge3/envs/py313-test
            shell level : 2
       user config file : /home/username/.condarc
 populated config files : /home/username/miniforge3/.condarc
                          /home/username/.condarc
          conda version : 24.11.3
    conda-build version : not installed
         python version : 3.10.14.final.0
                 solver : libmamba (default)
       virtual packages : __archspec=1=zen3
                          __conda=24.11.3=0
                          __glibc=2.36=0
                          __linux=6.1.0=0
                          __unix=0=0
       base environment : /home/username/miniforge3  (writable)
      conda av data dir : /home/username/miniforge3/etc/conda
  conda av metadata url : None
           channel URLs : https://conda.anaconda.org/conda-forge/linux-64
                          https://conda.anaconda.org/conda-forge/noarch
                          https://repo.anaconda.com/pkgs/main/linux-64
                          https://repo.anaconda.com/pkgs/main/noarch
                          https://repo.anaconda.com/pkgs/r/linux-64
                          https://repo.anaconda.com/pkgs/r/noarch
          package cache : /home/username/miniforge3/pkgs
                          /home/username/.conda/pkgs
       envs directories : /home/username/miniforge3/envs
                          /home/username/.conda/envs
               platform : linux-64
             user-agent : conda/24.11.3 requests/2.31.0 CPython/3.10.14 Linux/6.1.0-47-amd64 debian/12.6 glibc/2.36 solver/libmamba conda-libmamba-solver/24.1.0 libmambapy/1.5.8
                UID:GID : 10446:115
             netrc file : None
           offline mode : False

[rossjjennings]

This looks very similar to the issue I just opened for Python 3.12.14 build h5f976f7_2_cpython (#924, opened within 5 minutes of this one 😅)!

[h-vetinari]

Fixed already by #920