python-msgspec fails to build with Python 3.14.0a1. gcc -fno-strict-overflow -Wsign-compare -DDYNAMIC_ANNOTATIONS_ENABLED=1 -DNDEBUG -fexceptions -fcf-protection -fexceptions -fcf-protection -fexceptions -fcf-protection -O3 -O2 -flto=auto -ffat-lto-objects -fexceptions -g -grecord-gcc-switches -pipe -Wall -Werror=format-security -Wp,-U_FORTIFY_SOURCE,-D_FORTIFY_SOURCE=3 -Wp,-D_GLIBCXX_ASSERTIONS -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -fstack-protector-strong -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -march=x86-64 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection -mtls-dialect=gnu2 -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer -fPIC -I/usr/include/python3.14 -c msgspec/_core.c -o build/temp.linux-x86_64-cpython-314/msgspec/_core.o msgspec/_core.c:2142:7: error: ‘_Py_IMMORTAL_REFCNT’ undeclared here (not in a function) 2142 | { _Py_IMMORTAL_REFCNT }, | ^~~~~~~~~~~~~~~~~~~ error: command '/usr/bin/gcc' failed with exit code 1 error: subprocess-exited-with-error https://docs.python.org/3.14/whatsnew/3.14.html For the build logs, see: https://copr-be.cloud.fedoraproject.org/results/@python/python3.14/fedora-rawhide-x86_64/08189210-python-msgspec/ For all our attempts to build python-msgspec with Python 3.14, see: https://copr.fedorainfracloud.org/coprs/g/python/python3.14/package/python-msgspec/ Testing and mass rebuild of packages is happening in copr. You can follow these instructions to test locally in mock if your package builds with Python 3.14: https://copr.fedorainfracloud.org/coprs/g/python/python3.14/ Let us know here if you have any questions. Python 3.14 is planned to be included in Fedora 43. To make that update smoother, we're building Fedora packages with all pre-releases of Python 3.14. A build failure prevents us from testing all dependent packages (transitive [Build]Requires), so if this package is required a lot, it's important for us to get it fixed soon. We'd appreciate help from the people who know this package best, but if you don't want to work on this now, let us know so we can try to work around it on our side.
Backporting that PR gives: + /usr/bin/pytest ============================= test session starts ============================== platform linux -- Python 3.14.0a3, pytest-8.3.4, pluggy-1.5.0 rootdir: /builddir/build/BUILD/python-msgspec-0.18.6-build/msgspec-0.18.6 configfile: setup.cfg collected 5652 items / 3 errors / 2 skipped ==================================== ERRORS ==================================== ____________________ ERROR collecting tests/test_struct.py _____________________ tests/test_struct.py:828: in <module> FrozenPoint(1, 2), E TypeError: Extra positional arguments provided _____________________ ERROR collecting tests/test_toml.py ______________________ tests/test_toml.py:125: in <module> (ExStruct(1, "two"), ExStruct), E TypeError: Extra positional arguments provided _____________________ ERROR collecting tests/test_yaml.py ______________________ tests/test_yaml.py:105: in <module> (ExStruct(1, "two"), ExStruct), E TypeError: Extra positional arguments provided =========================== short test summary info ============================ ERROR tests/test_struct.py - TypeError: Extra positional arguments provided ERROR tests/test_toml.py - TypeError: Extra positional arguments provided ERROR tests/test_yaml.py - TypeError: Extra positional arguments provided !!!!!!!!!!!!!!!!!!! Interrupted: 3 errors during collection !!!!!!!!!!!!!!!!!!!! ========================= 2 skipped, 3 errors in 1.16s =========================
So does updating to 0.19.0. Perhaps this needs to be reported upstream.
Reported as https://github.com/jcrist/msgspec/issues/795
This bug appears to have been reported against 'rawhide' during the Fedora Linux 42 development cycle. Changing version to 42.
FEDORA-2025-021924116d (python-msgspec-0.19.0-2.fc43) has been submitted as an update to Fedora 43. https://bodhi.fedoraproject.org/updates/FEDORA-2025-021924116d
FEDORA-2025-021924116d (python-msgspec-0.19.0-2.fc43) has been pushed to the Fedora 43 stable repository. If problem still persists, please make note of it in this bug report.