#1097676 python-cython-blis: ftbfs with GCC-15

#1097676#5
Date:
2025-02-17 17:46:47 UTC
From:
To:
[This bug is NOT targeted to the upcoming trixie release]

Please keep this issue open in the bug tracker for the package it
was filed for.  If a fix in another package is required, please
file a bug for the other package (or clone), and add a block in this
package. Please keep the issue open until the package can be built in
a follow-up test rebuild.

The package fails to build in a test rebuild on at least amd64 with
gcc-15/g++-15, but succeeds to build with gcc-14/g++-14. The
severity of this report will be raised before the forky release.

The full build log can be found at:
http://qa-logs.debian.net/2025/02/16/amd64exp/python-cython-blis_1.0.0-1_unstable_gccexp.log.gz
The last lines of the build log are at the end of this report.

To build with GCC 15, either set CC=gcc-15 CXX=g++-15 explicitly,
or install the gcc, g++, gfortran, ... packages from experimental.

  apt-get -t=experimental install g++

GCC 15 now defaults to the C23/C++23 standards, exposing many FTBFS.
Other Common build failures are new warnings resulting in build failures
with -Werror turned on, or new/dropped symbols in Debian symbols files.
For other C/C++ related build failures see the porting guide at
http://gcc.gnu.org/gcc-15/porting_to.html

[...]
[COMMAND] gcc -c /build/reproducible-path/python-cython-blis-1.0.0/blis/_src/config/steamroller/bli_cntx_init_steamroller.c -o /tmp/tmpe37_6kbl/bli_cntx_init_steamroller.o -O2 -fPIC -std=c99 -D_POSIX_C_SOURCE=200112L -DBLIS_VERSION_STRING="0.9.0" -DBLIS_IS_BUILDING_LIBRARY -Iinclude/linux-x86_64 -I./frame/3/ -I./frame/1m/ -I./frame/1f/ -I./frame/1/ -I./frame/include -I/build/reproducible-path/python-cython-blis-1.0.0/blis/_src/include/linux-x86_64
[COMMAND] gcc -c /build/reproducible-path/python-cython-blis-1.0.0/blis/_src/config/zen/bli_cntx_init_zen.c -o /tmp/tmpe37_6kbl/bli_cntx_init_zen.o -O2 -fomit-frame-pointer -fPIC -std=c99 -D_POSIX_C_SOURCE=200112L -DBLIS_VERSION_STRING="0.9.0" -DBLIS_IS_BUILDING_LIBRARY -Iinclude/linux-x86_64 -I./frame/3/ -I./frame/1m/ -I./frame/1f/ -I./frame/1/ -I./frame/include -I/build/reproducible-path/python-cython-blis-1.0.0/blis/_src/include/linux-x86_64
[COMMAND] gcc -c /build/reproducible-path/python-cython-blis-1.0.0/blis/_src/config/zen2/bli_cntx_init_zen2.c -o /tmp/tmpe37_6kbl/bli_cntx_init_zen2.o -O2 -fomit-frame-pointer -fPIC -std=c99 -D_POSIX_C_SOURCE=200112L -DBLIS_VERSION_STRING="0.9.0" -DBLIS_IS_BUILDING_LIBRARY -Iinclude/linux-x86_64 -I./frame/3/ -I./frame/1m/ -I./frame/1f/ -I./frame/1/ -I./frame/include -I/build/reproducible-path/python-cython-blis-1.0.0/blis/_src/include/linux-x86_64
[COMMAND] gcc -c /build/reproducible-path/python-cython-blis-1.0.0/blis/_src/config/zen3/bli_cntx_init_zen3.c -o /tmp/tmpe37_6kbl/bli_cntx_init_zen3.o -O3 -fPIC -std=c99 -D_POSIX_C_SOURCE=200112L -DBLIS_VERSION_STRING="0.9.0" -DBLIS_IS_BUILDING_LIBRARY -Iinclude/linux-x86_64 -I./frame/3/ -I./frame/1m/ -I./frame/1f/ -I./frame/1/ -I./frame/include -I/build/reproducible-path/python-cython-blis-1.0.0/blis/_src/include/linux-x86_64gcc: error: unrecognized command-line option ‘-mavx512pf’; did you mean ‘-mavx512f’?

[COMMAND] gcc -c /build/reproducible-path/python-cython-blis-1.0.0/blis/_src/kernels/skx/3/bli_dgemm_skx_asm_16x12_l2.c -o /tmp/tmpe37_6kbl/bli_dgemm_skx_asm_16x12_l2.o -O2 -O3 -fomit-frame-pointer -mavx512f -mavx512dq -mavx512bw -mavx512vl -mfpmath=sse -march=skylake-avx512 -fPIC -std=c99 -D_POSIX_C_SOURCE=200112L -DBLIS_VERSION_STRING="0.9.0" -DBLIS_IS_BUILDING_LIBRARY -Iinclude/linux-x86_64 -I./frame/3/ -I./frame/1m/ -I./frame/1f/ -I./frame/1/ -I./frame/include -I/build/reproducible-path/python-cython-blis-1.0.0/blis/_src/include/linux-x86_64
[COMMAND] gcc -c /build/reproducible-path/python-cython-blis-1.0.0/blis/_src/kernels/skx/3/bli_dgemm_skx_asm_16x14.c -o /tmp/tmpe37_6kbl/bli_dgemm_skx_asm_16x14.o -O2 -O3 -fomit-frame-pointer -mavx512f -mavx512dq -mavx512bw -mavx512vl -mfpmath=sse -march=skylake-avx512 -fPIC -std=c99 -D_POSIX_C_SOURCE=200112L -DBLIS_VERSION_STRING="0.9.0" -DBLIS_IS_BUILDING_LIBRARY -Iinclude/linux-x86_64 -I./frame/3/ -I./frame/1m/ -I./frame/1f/ -I./frame/1/ -I./frame/include -I/build/reproducible-path/python-cython-blis-1.0.0/blis/_src/include/linux-x86_64
[COMMAND] gcc -c /build/reproducible-path/python-cython-blis-1.0.0/blis/_src/kernels/skx/3/bli_sgemm_skx_asm_32x12_l2.c -o /tmp/tmpe37_6kbl/bli_sgemm_skx_asm_32x12_l2.o -O2 -O3 -fomit-frame-pointer -mavx512f -mavx512dq -mavx512bw -mavx512vl -mfpmath=sse -march=skylake-avx512 -fPIC -std=c99 -D_POSIX_C_SOURCE=200112L -DBLIS_VERSION_STRING="0.9.0" -DBLIS_IS_BUILDING_LIBRARY -Iinclude/linux-x86_64 -I./frame/3/ -I./frame/1m/ -I./frame/1f/ -I./frame/1/ -I./frame/include -I/build/reproducible-path/python-cython-blis-1.0.0/blis/_src/include/linux-x86_64
[COMMAND] gcc -c /build/reproducible-path/python-cython-blis-1.0.0/blis/_src/kernels/knl/1m/bli_dpackm_knl_asm_24x8.c -o /tmp/tmpe37_6kbl/bli_dpackm_knl_asm_24x8.o -O2 -O3 -mavx512f -mavx512pf -mfpmath=sse -march=knl -fPIC -std=c99 -D_POSIX_C_SOURCE=200112L -DBLIS_VERSION_STRING="0.9.0" -DBLIS_IS_BUILDING_LIBRARY -Iinclude/linux-x86_64 -I./frame/3/ -I./frame/1m/ -I./frame/1f/ -I./frame/1/ -I./frame/include -I/build/reproducible-path/python-cython-blis-1.0.0/blis/_src/include/linux-x86_64
Traceback (most recent call last):
  File "/build/reproducible-path/python-cython-blis-1.0.0/setup.py", line 327, in <module>
    setup(
    ~~~~~^
        setup_requires=[
        ^^^^^^^^^^^^^^^^
    ...<47 lines>...
        ],
        ^^
    )
    ^
  File "/usr/lib/python3/dist-packages/setuptools/__init__.py", line 117, in setup
    return distutils.core.setup(**attrs)
           ~~~~~~~~~~~~~~~~~~~~^^^^^^^^^
  File "/usr/lib/python3/dist-packages/setuptools/_distutils/core.py", line 183, in setup
    return run_commands(dist)
  File "/usr/lib/python3/dist-packages/setuptools/_distutils/core.py", line 199, in run_commands
    dist.run_commands()
    ~~~~~~~~~~~~~~~~~^^
  File "/usr/lib/python3/dist-packages/setuptools/_distutils/dist.py", line 954, in run_commands
    self.run_command(cmd)
    ~~~~~~~~~~~~~~~~^^^^^
  File "/usr/lib/python3/dist-packages/setuptools/dist.py", line 995, in run_command
    super().run_command(command)
    ~~~~~~~~~~~~~~~~~~~^^^^^^^^^
  File "/usr/lib/python3/dist-packages/setuptools/_distutils/dist.py", line 973, in run_command
    cmd_obj.run()
    ~~~~~~~~~~~^^
  File "/usr/lib/python3/dist-packages/setuptools/_distutils/command/build.py", line 135, in run
    self.run_command(cmd_name)
    ~~~~~~~~~~~~~~~~^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/setuptools/_distutils/cmd.py", line 316, in run_command
    self.distribution.run_command(command)
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^
  File "/usr/lib/python3/dist-packages/setuptools/dist.py", line 995, in run_command
    super().run_command(command)
    ~~~~~~~~~~~~~~~~~~~^^^^^^^^^
  File "/usr/lib/python3/dist-packages/setuptools/_distutils/dist.py", line 973, in run_command
    cmd_obj.run()
    ~~~~~~~~~~~^^
  File "/usr/lib/python3/dist-packages/setuptools/command/build_ext.py", line 99, in run
    _build_ext.run(self)
    ~~~~~~~~~~~~~~^^^^^^
  File "/usr/lib/python3/dist-packages/setuptools/_distutils/command/build_ext.py", line 359, in run
    self.build_extensions()
    ~~~~~~~~~~~~~~~~~~~~~^^
  File "/build/reproducible-path/python-cython-blis-1.0.0/setup.py", line 116, in build_extensions
    objects = self.compile_objects(platform_name, arch, OBJ_DIR)
  File "/build/reproducible-path/python-cython-blis-1.0.0/setup.py", line 258, in compile_objects
    objects.append(self.build_object(env=env, **spec))
                   ~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^
  File "/build/reproducible-path/python-cython-blis-1.0.0/setup.py", line 273, in build_object
    subprocess.check_call(command, cwd=BLIS_DIR)
    ~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.13/subprocess.py", line 421, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['gcc', '-c', '/build/reproducible-path/python-cython-blis-1.0.0/blis/_src/kernels/knl/1m/bli_dpackm_knl_asm_24x8.c', '-o', '/tmp/tmpe37_6kbl/bli_dpackm_knl_asm_24x8.o', '-O2', '-O3', '-mavx512f', '-mavx512pf', '-mfpmath=sse', '-march=knl', '-fPIC', '-std=c99', '-D_POSIX_C_SOURCE=200112L', '-DBLIS_VERSION_STRING="0.9.0"', '-DBLIS_IS_BUILDING_LIBRARY', '-Iinclude/linux-x86_64', '-I./frame/3/', '-I./frame/1m/', '-I./frame/1f/', '-I./frame/1/', '-I./frame/include', '-I/build/reproducible-path/python-cython-blis-1.0.0/blis/_src/include/linux-x86_64']' returned non-zero exit status 1.
E: pybuild pybuild:389: build: plugin distutils failed with: exit code=1: /usr/bin/python3 setup.py build
dh_auto_build: error: pybuild --build -i python{version} -p "3.12 3.13" returned exit code 13
make: *** [debian/rules:10: binary] Error 25
dpkg-buildpackage: error: debian/rules binary subprocess returned exit status 2

#1097676#14
Date:
2026-09-11 21:05:28 UTC
From:
To:
user debian-python@lists.debian.org
usertags 1097676 python3.15
tags 1097676 patch
thanks

Hi!

While rebuilding the python related packages against the Python 3.15rc2
version I ran into this FTBFS [1].

To fix the problems I had to:
- Add upstream commit 1498af063ea924e2e2334a3f5ab49ae1a66a8648 — Disable
   obsolete AVX512 flags (removes - mavx512pf and -mno-avx512pf
   -mno-avx512er)
- Add upstream commit 89c1f0dd0933032a56e334bdbc047b9abdc19ed1 — Remove
   -march=knl flag for GCC 15 compatibility (removes -march=knl on
   optimized KNL kernels and switches to -march=skylake on reference KNL
   kernels)
- Add upstream commit 6b970700a6fa352d71e1ea14ca44c5f39ce1c770 Apply
   temporary fix for gcc 15.
- Add patch to remove unused blis.cy imports in test_dotv

I've applied these fixes in the sandbox [2] to verify that it builds
successfully, these should be applied in Debian to get the package back
to a healthy state.

Happy hacking,

[1]: https://debusine.debian.net/debian/r-python-python3.15/artifact/4587725/
[2]: https://debusine.debian.net/debian/r-python-python3.15/

#1097676#21
Date:
2026-10-05 19:50:09 UTC
From:
To:
We believe that the bug you reported is fixed in the latest version of
python-cython-blis, which is due to be installed in the Debian FTP archive.

A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 1097676@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Alexandre Detiste <tchet@debian.org> (supplier of updated python-cython-blis package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster@ftp-master.debian.org)
Format: 1.8
Date: Mon, 05 Oct 2026 20:52:45 +0200
Source: python-cython-blis
Architecture: source
Version: 1.0.0-3
Distribution: unstable
Urgency: medium
Maintainer: Debian Science Maintainers <debian-science-maintainers@lists.alioth.debian.org>
Changed-By: Alexandre Detiste <tchet@debian.org>
Closes: 1097676
Changes:
 python-cython-blis (1.0.0-3) unstable; urgency=medium
 .
   * Team upload.
 .
   [ Maximiliano Curia ]
   * Fix ftbfs with GCC-15 (Closes: #1097676)
 .
   [ Alexandre Detiste ]
   * Remove redundant Priority: optional from source stanza.
   * Update standards version to 4.7.4, no changes needed.
   * drop "Rules-Requires-Root: no": it is the default now
   * rewrite d/watch in v5 format, detect 1.3.3 version
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