Dear maintainer:

During a rebuild of all packages in unstable, this package failed to build.

Below you will find the last part of the build log (probably the most
relevant part, but not necessarily). If required, the full build log
is available here:

https://people.debian.org/~sanvila/build-logs/202512/

About the archive rebuild: The build was made on virtual machines from AWS,
using sbuild and a reduced chroot with only build-essential packages.

If you cannot reproduce the bug please contact me privately, as I
am willing to provide ssh access to a virtual machine where the bug is
fully reproducible.

If this is really a bug in one of the build-depends, please use
reassign and add an affects on src:qcelemental, so that this is still
visible in the BTS web page for this package.

Thanks.
--------------------------------------------------------------------------------
[...]
 debian/rules clean
dh clean --with=python3 --buildsystem=pybuild
   dh_auto_clean -O--buildsystem=pybuild
   dh_autoreconf_clean -O--buildsystem=pybuild
   dh_clean -O--buildsystem=pybuild
 debian/rules binary
dh binary --with=python3 --buildsystem=pybuild
   dh_update_autotools_config -O--buildsystem=pybuild
   dh_autoreconf -O--buildsystem=pybuild
   dh_auto_configure -O--buildsystem=pybuild
   dh_auto_build -O--buildsystem=pybuild
I: pybuild plugin_pyproject:131: Building wheel for python3.14 with "build" module
I: pybuild base:317: python3.14 -m build --skip-dependency-check --no-isolation --wheel --outdir /<<PKGBUILDDIR>>/.pybuild/cpython3_3.14
* Building wheel...
Successfully built qcelemental-0.29.0-py3-none-any.whl
I: pybuild plugin_pyproject:155: Unpacking wheel built for python3.14 with "installer" module
I: pybuild plugin_pyproject:131: Building wheel for python3.13 with "build" module
I: pybuild base:317: python3.13 -m build --skip-dependency-check --no-isolation --wheel --outdir /<<PKGBUILDDIR>>/.pybuild/cpython3_3.13
* Building wheel...
Successfully built qcelemental-0.29.0-py3-none-any.whl
I: pybuild plugin_pyproject:155: Unpacking wheel built for python3.13 with "installer" module
   debian/rules override_dh_auto_test
make[1]: Entering directory '/<<PKGBUILDDIR>>'
dh_auto_test
I: pybuild base:317: cd /<<PKGBUILDDIR>>/.pybuild/cpython3_3.14/build; python3.14 -m pytest
============================= test session starts ==============================
platform linux -- Python 3.14.2, pytest-9.0.2, pluggy-1.6.0
rootdir: /<<PKGBUILDDIR>>/.pybuild/cpython3_3.14/build
configfile: pyproject.toml
plugins: cov-5.0.0, typeguard-4.4.4
collected 0 items / 1 error

==================================== ERRORS ====================================

reassign 1123331 python3-pydantic
affects 1123331 src:qcelemental
found 1123331 2.12.5-2
close 1123331 2.13.3-1
thanks

This problem fixed by itself without requiring any change in qcelemental.

So I did a debbisect and this was the outcome:

bisection finished successfully
  last bad timestamp: 20260505T142927Z
  first good timestamp: 20260506T023405Z
the following packages differ between the last bad and first good timestamp:
  python3-pydantic 2.12.5-2 -> 2.13.3-1
  python3-pydantic-core 2.41.5-5 -> 2.46.3-1

I'm choosing python3-pydantic because it's in debian/control as an
explicit build-dependency.

Thanks.

This makes sense, because the failure mentioned pydantic.v1 and was for
Python 3.14 only, and:

"This release contains the updated `pydantic.v1` namespace, matching
version 1.10.26 which includes support for Python 3.14."