Incompatible function type building pasteboard._native

[xdgc]

Firstly I want to acknowledge that Toby is not actively maintaining pasteboard, but I do want to document this issue in case others have it.

I'm on a new Mac, and am reinstalling all the things. I'm on macOS 15.5 (Sequoia), and just installed Homebrew. However I get errors building pasteboard on either Apple Python or Homebrew's.

      building 'pasteboard._native' extension
      gcc -fno-strict-overflow -Wsign-compare -Wunreachable-code -fno-common -dynamic -DNDEBUG -g -O3 -Wall -isysroot /Library/Developer/CommandLineTools/SDKs/MacOSX15.sdk -I/opt/homebrew/opt/python@3.12/Frameworks/Python.framework/Versions/3.12/include/python3.12 -c src/pasteboard/pasteboard.m -o build/temp.macosx-15.0-arm64-cpython-312/src/pasteboard/pasteboard.o -Wall -Wextra -Wpedantic -Werror
      src/pasteboard/pasteboard.m:325:9: error: cast from 'PyObject *(*)(PyObject *, PyObject *, PyObject *)' (aka 'struct _object *(*)(struct _object *, struct _object *, struct _object *)') to 'PyCFunction' (aka 'struct _object *(*)(struct _object *, struct _object *)') converts to incompatible function type [-Werror,-Wcast-function-type-mismatch]
        325 |         (PyCFunction)pasteboard_get_contents,
            |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      src/pasteboard/pasteboard.m:331:9: error: cast from 'PyObject *(*)(PyObject *, PyObject *, PyObject *)' (aka 'struct _object *(*)(struct _object *, struct _object *, struct _object *)') to 'PyCFunction' (aka 'struct _object *(*)(struct _object *, struct _object *)') converts to incompatible function type [-Werror,-Wcast-function-type-mismatch]
        331 |         (PyCFunction)pasteboard_set_contents,
            |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      src/pasteboard/pasteboard.m:337:9: error: cast from 'PyObject *(*)(PyObject *, PyObject *, PyObject *)' (aka 'struct _object *(*)(struct _object *, struct _object *, struct _object *)') to 'PyCFunction' (aka 'struct _object *(*)(struct _object *, struct _object *)') converts to incompatible function type [-Werror,-Wcast-function-type-mismatch]
        337 |         (PyCFunction)pasteboard_get_file_urls,
            |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      3 errors generated.
      error: command '/usr/bin/gcc' failed with exit code 1

From minimal research I believe that the cast to PyCFunction is correct per the Python API specification, but that gcc/clang is overly complainy about it because a PyCFunctionWithKeywords is a valid implementation for this method table.

I "solved" the problem by adding "-Wno-cast-function-type-mismatch" to the end of setup.py's extra_compile_args, superseding the macro warn options.