Free-threaded Python Library Compatibility Checker

t call last):
        File "/tmp/pip-build-env-vmsbyqfe/overlay/lib/python3.14t/site-packages/setuptools/_distutils/compilers/C/unix.py", line 217, in _compile
          self.spawn(
          ~~~~~~~~~~^
              compiler_so_cxx + cc_args + [src, '-o', obj] + extra_postargs
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
          )
          ^
        File "/tmp/pip-install-auneqktn/grpcio_13c2cc17f70042be8a9e504dd4c8cbf9/src/python/grpcio/_spawn_patch.py", line 66, in _commandfile_spawn
          _classic_spawn(self, command, **kwargs)
          ~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^
        File "/tmp/pip-build-env-vmsbyqfe/overlay/lib/python3.14t/site-packages/setuptools/_distutils/compilers/C/base.py", line 1158, in spawn
          spawn(cmd, dry_run=self.dry_run, **kwargs)
          ~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "/tmp/pip-build-env-vmsbyqfe/overlay/lib/python3.14t/site-packages/setuptools/_distutils/spawn.py", line 93, in spawn
          raise DistutilsExecError(
              f"command {_debug(cmd)!r} failed with exit code {err.returncode}"
          ) from err
      distutils.errors.DistutilsExecError: command '/usr/bin/c++' failed with exit code 1
      
      During handling of the above exception, another exception occurred:
      
      Traceback (most recent call last):
        File "/tmp/pip-install-auneqktn/grpcio_13c2cc17f70042be8a9e504dd4c8cbf9/src/python/grpcio/commands.py", line 282, in build_extensions
          build_ext.build_ext.build_extensions(self)
          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^
        File "/tmp/pip-build-env-vmsbyqfe/overlay/lib/python3.14t/site-packages/setuptools/_distutils/command/build_ext.py", line 484, in build_extensions
          self._build_extensions_serial()
          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^
        File "/tmp/pip-build-env-vmsbyqfe/overlay/lib/python3.14t/site-packages/setuptools/_distutils/command/build_ext.py", line 510, in _build_extensions_serial
          self.build_extension(ext)
          ~~~~~~~~~~~~~~~~~~~~^^^^^
        File "/tmp/pip-build-env-vmsbyqfe/overlay/lib/python3.14t/site-packages/setuptools/command/build_ext.py", line 264, in build_extension
          _build_ext.build_extension(self, ext)
          ~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^
        File "/tmp/pip-build-env-vmsbyqfe/overlay/lib/python3.14t/site-packages/setuptools/_distutils/command/build_ext.py", line 565, in build_extension
          objects = self.compiler.compile(
              sources,
          ...<5 lines>...
              depends=ext.depends,
          )
        File "/tmp/pip-install-auneqktn/grpcio_13c2cc17f70042be8a9e504dd4c8cbf9/src/python/grpcio/_parallel_compile_patch.py", line 70, in _parallel_compile
          multiprocessing.pool.ThreadPool(BUILD_EXT_COMPILER_JOBS).map(
          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
              _compile_single_file, objects
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
          )
          ^
        File "/root/.local/share/uv/python/cpython-3.14.0a6+freethreaded-linux-x86_64-gnu/lib/python3.14t/multiprocessing/pool.py", line 367, in map
          return self._map_async(func, iterable, mapstar, chunksize).get()
                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^
        File "/root/.local/share/uv/python/cpython-3.14.0a6+freethreaded-linux-x86_64-gnu/lib/python3.14t/multiprocessing/pool.py", line 774, in get
          raise self._value
        File "/root/.local/share/uv/python/cpython-3.14.0a6+freethreaded-linux-x86_64-gnu/lib/python3.14t/multiprocessing/pool.py", line 125, in worker
          result = (True, func(*args, **kwds))
                          ~~~~^^^^^^^^^^^^^^^
        File "/root/.local/share/uv/python/cpython-3.14.0a6+freethreaded-linux-x86_64-gnu/lib/python3.14t/multiprocessing/pool.py", line 48, in mapstar
          return list(map(*args))
        File "/tmp/pip-install-auneqktn/grpcio_13c2cc17f70042be8a9e504dd4c8cbf9/src/python/grpcio/_parallel_compile_patch.py", line 65, in _compile_single_file
          self._compile(obj, src, ext, cc_args, extra_postargs, pp_opts)
          ~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "/tmp/pip-install-auneqktn/grpcio_13c2cc17f70042be8a9e504dd4c8cbf9/src/python/grpcio/commands.py", line 264, in new_compile
          return old_compile(obj, src, ext, cc_args, extra_postargs, pp_opts)
        File "/tmp/pip-build-env-vmsbyqfe/overlay/lib/python3.14t/site-packages/setuptools/_distutils/compilers/C/unix.py", line 223, in _compile
          raise CompileError(msg)
      distutils.compilers.C.errors.CompileError: command '/usr/bin/c++' failed with exit code 1
      
      [end of output]
  
  note: This error originates from a subprocess, and is likely not a problem with pip.
  ERROR: Failed building wheel for grpcio
ERROR: Failed to build installable wheels for some pyproject.toml based projects (grpcio-tools, grpcio)

  error: subprocess-exited-with-error
  
  × Preparing metadata (pyproject.toml) did not run successfully.
  │ exit code: 1
  ╰─> [10 lines of output]
      Checking for Rust toolchain....
      Running `maturin pep517 write-dist-info --metadata-directory /tmp/pip-modern-metadata-ih8cuh55 --interpreter /tmp/tmp6gg0tng4/venv/bin/python`
      error: failed to parse lock file at: /tmp/pip-install-fvbm25hn/rpds-py_67a5b37c69164f6baab20d96ae129a2f/Cargo.lock
      
      Caused by:
        lock file version `4` was found, but this version of Cargo does not understand this lock file, perhaps Cargo needs to be updated?
      💥 maturin failed
        Caused by: Cargo metadata failed. Does your crate compile with `cargo build`?
        Caused by: `cargo metadata` exited with an error:
      Error running maturin: Command '['maturin', 'pep517', 'write-dist-info', '--metadata-directory', '/tmp/pip-modern-metadata-ih8cuh55', '--interpreter', '/tmp/tmp6gg0tng4/venv/bin/python']' returned non-zero exit status 1.
      [end of output]
  
  note: This error originates from a subprocess, and is likely not a problem with pip.
error: metadata-generation-failed

× Encountered error while generating package metadata.
╰─> See above for output.

note: This is an issue with the package mentioned above, not pip.
hint: See above for details.

  error: subprocess-exited-with-error
  
  × Building wheel for pydantic-core (pyproject.toml) did not run successfully.
  │ exit code: 1
  ╰─> [13 lines of output]
      Running `maturin pep517 build-wheel -i /tmp/tmptnze47kg/venv/bin/python --compatibility off`
      📦 Including license file "/tmp/pip-install-niamqvnu/pydantic-core_d96f85231861484cb7d5ef33bdb11b07/LICENSE"
      🍹 Building a mixed python/rust project
      🔗 Found pyo3 bindings
      🐍 Found CPython 3.14t at /tmp/tmptnze47kg/venv/bin/python
      📡 Using build options features, bindings from pyproject.toml
      warning: unused manifest key: lints
      error: package `pydantic-core v2.34.1 (/tmp/pip-install-niamqvnu/pydantic-core_d96f85231861484cb7d5ef33bdb11b07)` cannot be built because it requires rustc 1.75 or newer, while the currently active rustc version is 1.63.0
      
      💥 maturin failed
        Caused by: Failed to build a native library through cargo
        Caused by: Cargo build finished with "exit status: 101": `env -u CARGO PYO3_ENVIRONMENT_SIGNATURE="cpython-3.14-64bit" PYO3_PYTHON="/tmp/tmptnze47kg/venv/bin/python" PYTHON_SYS_EXECUTABLE="/tmp/tmptnze47kg/venv/bin/python" "cargo" "rustc" "--features" "pyo3/extension-module" "--message-format" "json-render-diagnostics" "--manifest-path" "/tmp/pip-install-niamqvnu/pydantic-core_d96f85231861484cb7d5ef33bdb11b07/Cargo.toml" "--release" "--lib"`
      Error: command ['maturin', 'pep517', 'build-wheel', '-i', '/tmp/tmptnze47kg/venv/bin/python', '--compatibility', 'off'] returned non-zero exit status 1
      [end of output]
  
  note: This error originates from a subprocess, and is likely not a problem with pip.
  ERROR: Failed building wheel for pydantic-core
ERROR: Failed to build installable wheels for some pyproject.toml based projects (pydantic-core)