Build error by using `stdscr` in `curses` C extension module

[picnixz]

Bug report

Bug description:

I wanted to compile Python but I got the following issue since #151748

In file included from ./Modules/_curses_panel.c:21:
./Include/py_curses.h:99:5: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
 99 | PyObject *stdscr; /* the screen's standard window, or NULL */
 | ^~~~~~~~
In file included from /usr/include/ncursesw/curses.h:90,
 from ./Include/py_curses.h:47:
./Include/py_curses.h:99:15: error: field ‘_nc_stdscr’ declared as a function
 99 | PyObject *stdscr; /* the screen's standard window, or NULL */
 | ^~~~~~
make: *** [Makefile:3791: Modules/_curses_panel.o] Error 1
make: *** Waiting for unfinished jobs....
In file included from ./Modules/_cursesmodule.c:108:
./Include/py_curses.h:99:5: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
 99 | PyObject *stdscr; /* the screen's standard window, or NULL */
 | ^~~~~~~~
In file included from /usr/include/ncursesw/curses.h:90,
 from ./Include/py_curses.h:47:
./Include/py_curses.h:99:15: error: field ‘_nc_stdscr’ declared as a function
 99 | PyObject *stdscr; /* the screen's standard window, or NULL */
 | ^~~~~~
./Modules/_cursesmodule.c:5128:20: warning: function declaration isn’t a prototype [-Wstrict-prototypes]
 5128 | FILE *outfp, FILE *infp, PyObject *stdscr)
 | ^~~~
./Modules/_cursesmodule.c: In function ‘PyCursesScreen_New’:
./Modules/_cursesmodule.c:5138:16: error: lvalue required as left operand of assignment
 5138 | so->stdscr = Py_XNewRef(stdscr);
 | ^
In file included from ./Include/Python.h:80,
 from ./Modules/_cursesmodule.c:96:
./Modules/_cursesmodule.c: In function ‘PyCursesScreen_clear’:
./Include/refcount.h:485:39: error: lvalue required as unary ‘&’ operand
 485 | _Py_TYPEOF(op)* _tmp_op_ptr = &(op); \
 | ^
./Modules/_cursesmodule.c:5200:5: note: in expansion of macro ‘Py_CLEAR’
 5200 | Py_CLEAR(so->stdscr);
 | ^~~~~~~~
./Modules/_cursesmodule.c: In function ‘_curses_newterm_impl’:
./Modules/_cursesmodule.c:6727:49: error: lvalue required as left operand of assignment
 6727 | ((PyCursesScreenObject *)screenobj)->stdscr = Py_NewRef(win);
 | ^
make: *** [Makefile:3789: Modules/_cursesmodule.o] Error 1

The problem is that my ncursesw/ncurses.h contains

#define stdscr NCURSES_PUBLIC_VAR(stdscr())

And thus using stdscr is not a valid identifier in the struct or in the parameter functions.

cc @serhiy-storchaka

CPython versions tested on:

CPython main branch

Operating systems tested on:

No response

Linked PRs

• gh-153009: Fix compilation of curses on platforms that define the stdscr macro #153010