Unable to compile on Python 3.11 alpha 5

[domdfcoding]

When running python3.11 -m pip wheel hpy --use-pep517 the output is as follows:

Collecting hpy
  Downloading hpy-0.0.3.tar.gz (172 kB)
     |████████████████████████████████| 172 kB 9.5 MB/s 
  Installing build dependencies ... done
  Getting requirements to build wheel ... done
  Installing backend dependencies ... done
    Preparing wheel metadata ... done
Building wheels for collected packages: hpy
  Building wheel for hpy (PEP 517) ... error
  ERROR: Command errored out with exit status 1:
   command: /home/domdf/.local/bin/python3.11 /home/domdf/python311/lib/python3.11/site-packages/pip/_vendor/pep517/in_process/_in_process.py build_wheel /tmp/tmp4xeykvcx
       cwd: /tmp/pip-wheel-9n1000e1/hpy_bf00928872e2496a9d116bd1dd260d92
  Complete output (37 lines):
  fatal: not a git repository (or any of the parent directories): .git
  running bdist_wheel
  running build
  running build_py
  running egg_info
  writing hpy.egg-info/PKG-INFO
  writing dependency_links to hpy.egg-info/dependency_links.txt
  writing entry points to hpy.egg-info/entry_points.txt
  writing requirements to hpy.egg-info/requires.txt
  writing top-level names to hpy.egg-info/top_level.txt
  listing git files failed - pretending there aren't any
  reading manifest file 'hpy.egg-info/SOURCES.txt'
  reading manifest template 'MANIFEST.in'
  adding license file 'LICENSE'
  running build_ext
  building 'hpy.universal' extension
  hpy/debug/src/debug_ctx_cpython.c: In function ‘debug_ctx_CallRealFunctionFromTrampoline’:
  hpy/debug/src/debug_ctx_cpython.c:162:20: error: dereferencing pointer to incomplete type ‘cpy_Py_buffer’ {aka ‘struct bufferinfo’}
    162 |             a->view->obj = NULL;
        |                    ^~
  hpy/debug/src/debug_ctx_cpython.c:165:36: warning: passing argument 3 of ‘_buffer_h2py’ from incompatible pointer type [-Wincompatible-pointer-types]
    165 |         _buffer_h2py(dctx, &hbuf, a->view);
        |                                   ~^~~~~~
        |                                    |
        |                                    cpy_Py_buffer * {aka struct bufferinfo *}
  hpy/debug/src/debug_ctx_cpython.c:41:78: note: expected ‘Py_buffer *’ {aka ‘struct <anonymous> *’} but argument is of type ‘cpy_Py_buffer *’ {aka ‘struct bufferinfo *’}
     41 | static void _buffer_h2py(HPyContext *dctx, const HPy_buffer *src, Py_buffer *dest)
        |                                                                   ~~~~~~~~~~~^~~~
  hpy/debug/src/debug_ctx_cpython.c:173:29: warning: passing argument 2 of ‘_buffer_py2h’ from incompatible pointer type [-Wincompatible-pointer-types]
    173 |         _buffer_py2h(dctx, a->view, &hbuf);
        |                            ~^~~~~~
        |                             |
        |                             cpy_Py_buffer * {aka struct bufferinfo *}
  hpy/debug/src/debug_ctx_cpython.c:56:61: note: expected ‘const Py_buffer *’ {aka ‘const struct <anonymous> *’} but argument is of type ‘cpy_Py_buffer *’ {aka ‘struct bufferinfo *’}
     56 | static void _buffer_py2h(HPyContext *dctx, const Py_buffer *src, HPy_buffer *dest)
        |                                            ~~~~~~~~~~~~~~~~~^~~
  error: command '/usr/bin/gcc' failed with exit code 1
  ----------------------------------------
  ERROR: Failed building wheel for hpy
Failed to build hpy
ERROR: Failed to build one or more wheels

The output is more or less the same when building from git, with some of the line numbers changing.

---

It looks like bufferinfo was removed in python/cpython#29991, which made it into alpha 5.

It's used here:

hpy/hpy/devel/include/hpy/cpy_types.h

Line 12 in dd702f5

typedef struct bufferinfo cpy_Py_buffer;

[steve-s]

AFAICS cpy_types.h tries to forward declare types from Python.h? It does that for Py_buffer too:

/* generally speaking, we can't #include Python.h, but there are a bunch of
 * types defined there that we need to use.  Here, we redefine all the types
 * we need, with a cpy_ prefix.
 */

typedef struct _object cpy_PyObject;
// ...
typedef struct bufferinfo cpy_Py_buffer;

the bufferinfo tag was, however, removed, so in Include/buffer.h it is not:

typedef struct bufferinfo {
  // ...
} Py_buffer;

but:

typedef struct {
  // ...
} Py_buffer;

@antocuni any suggestions?

[fangerer]

Just tried to build with Python 3.11.0 and got this:

hpy/devel/src/runtime/ctx_type.c:657:58: error: declaration of 'struct bufferinfo' will not be visible outside of this function [-Werror,-Wvisibility]
typedef int (*HPyGetBufferProc)(struct _object *, struct bufferinfo *, int);
                                                         ^
hpy/devel/src/runtime/ctx_type.c:658:63: error: declaration of 'struct bufferinfo' will not be visible outside of this function [-Werror,-Wvisibility]
typedef void (*HPyReleaseBufferProc)(struct _object *, struct bufferinfo *);
                                                              ^
hpy/devel/src/runtime/ctx_type.c:677:48: error: incompatible function pointer types assigning to 'getbufferproc' (aka 'int (*)(struct _object *, Py_buffer *, int)') from 'HPyGetBufferProc' (aka 'int (*)(struct _object *, struct bufferinfo *, int)') [-Werror,-Wincompatible-function-pointer-types]
                    buffer_procs->bf_getbuffer = (HPyGetBufferProc)src->slot.cpy_trampoline;
                                               ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
hpy/devel/src/runtime/ctx_type.c:687:52: error: incompatible function pointer types assigning to 'releasebufferproc' (aka 'void (*)(struct _object *, Py_buffer *)') from 'HPyReleaseBufferProc' (aka 'void (*)(struct _object *, struct bufferinfo *)') [-Werror,-Wincompatible-function-pointer-types]
                    buffer_procs->bf_releasebuffer = (HPyReleaseBufferProc)src->slot.cpy_trampoline;
                                                   ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4 errors generated