Get compiling again without (new) deprecation warnings from Cython.

All tests pass locally on 3.10 except one, reported earlier: test_no_refcycle_through_target (gevent.tests.test__threading_2.ThreadTests)
And a new one that is similar:    test_no_refcycle_through_target (__main__.ThreadTests)

I haven't tried to debug that yet.

_setuputils.py

@@ -249,9 +249,19 @@ def cythonize1(ext):
             # of Pyrex defines. Taking this kind of decision based on
             # the runtime environment of the build is wrong, it needs
             # to be taken at C compile time."
-            compile_time_env={
-                'PY39B1': sys.hexversion >= 0x030900B1,
-            },
+            #
+            # They also say, "The 'IF' statement is deprecated and
+            # will be removed in a future Cython version. Consider
+            # using runtime conditions or C macros instead. See
+            # https://github.com/cython/cython/issues/4310"
+            #
+            # And: " The 'DEF' statement is deprecated and will be
+            # removed in a future Cython version. Consider using
+            # global variables, constants, and in-place literals
+            # instead."
+            #compile_time_env={
+            #
+            #},
             # The common_utility_include_dir (not well documented)
             # causes Cython to emit separate files for much of the
             # static support code. Each of the modules then includes

setup.py

@@ -450,6 +450,7 @@ def run_setup(ext_modules):
             "Programming Language :: Python :: 3.8",
             "Programming Language :: Python :: 3.9",
             "Programming Language :: Python :: 3.10",
+            "Programming Language :: Python :: 3.11",
             "Programming Language :: Python :: Implementation :: CPython",
             "Programming Language :: Python :: Implementation :: PyPy",
             "Operating System :: MacOS :: MacOS X",

src/gevent/_compat.h

+#ifndef _COMPAT_H
+#define _COMPAT_H
+
+/**
+ * Compatibility helpers for things that are better handled at C
+ * compilation time rather than Cython code generation time.
+ */
+
+#include <Python.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#if PY_VERSION_HEX >= 0x30B00A6
+#  define GEVENT_PY311 1
+   /* _PyInterpreterFrame moved to the internal C API in Python 3.11 */
+#  include <internal/pycore_frame.h>
+#else
+#  define GEVENT_PY311 0
+#  define _PyCFrame CFrame
+#endif
+
+/* FrameType and CodeType changed a lot in 3.11. */
+#if GREENLET_PY311
+typedef PyObject PyFrameObject;
+#else
+#include <frameobject.h>
+#if PY_MAJOR_VERSION < 3 || PY_MINOR_VERSION < 9
+/* these were added in 3.9, though they officially became stable in 3.10 */
+static void* PyFrame_GetBack(PyFrameObject* frame)
+{
+    return (PyObject*)((PyFrameObject*)frame)->f_back;
+}
+
+static PyObject* PyFrame_GetCode(PyFrameObject* frame)
+{
+    return (PyObject*)((PyFrameObject*)frame)->f_code;
+}
+#endif /* support 3.8 and below. */
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* _COMPAT_H */

src/gevent/_gevent_cgreenlet.pxd

@@ -54,45 +54,19 @@ cdef inline void greenlet_init():
 
 ctypedef object CodeType
 
-IF PY39B1: # XXX: Move all of this to C includes. Pyrex defines are not appropriate, according to the Cython devs.
-    ctypedef object FrameType
-
-    cdef extern from "Python.h":
-        CodeType PyFrame_GetCode(FrameType frame)
-        void* PyFrame_GetBack(FrameType frame)
-
-ELSE:
-    cdef extern from "frameobject.h":
-        ctypedef class types.FrameType [object PyFrameObject]:
-            # We don't have PyFrame_GetCode, need to use the pointer directly
-            cdef CodeType f_code
-
-            # We can't declare this in the object as an object, because it's
-            # allowed to be NULL, and Cython can't handle that.
-            # We have to go through the python machinery to get a
-            # proper None instead, or use a function.
-            cdef void* f_back
-
-cdef extern from "frameobject.h":
+cdef extern from "_compat.h":
     int PyFrame_GetLineNumber(FrameType frame)
+    CodeType PyFrame_GetCode(FrameType frame)
+    void* PyFrame_GetBack(FrameType frame)
+    ctypedef class types.FrameType [object PyFrameObject]:
+        pass
 
 @cython.nonecheck(False)
 cdef inline FrameType get_f_back(FrameType frame):
-    IF PY39B1:
-        f_back = PyFrame_GetBack(frame)
-    ELSE:
-        f_back = frame.f_back
+    f_back = PyFrame_GetBack(frame)
     if f_back != NULL:
         return <FrameType>f_back
 
-cdef inline int get_f_lineno(FrameType frame):
-    return PyFrame_GetLineNumber(frame)
-
-cdef inline CodeType get_f_code(FrameType frame):
-    IF PY39B1:
-        return PyFrame_GetCode(frame)
-    ELSE:
-        return frame.f_code
 
 cdef void _init()
 
@@ -122,7 +96,7 @@ cdef class _Frame:
                newest_Frame=_Frame,
                newer_Frame=_Frame,
                older_Frame=_Frame)
-cdef inline _Frame _extract_stack(int limit)
+cdef _Frame _extract_stack(int limit)
 
 cdef class Greenlet(greenlet):
     cdef readonly object value

src/gevent/greenlet.py

@@ -56,9 +56,10 @@ locals()['get_my_hub'] = lambda s: s.parent
 locals()['get_generic_parent'] = lambda s: s.parent
 
 # Frame access
+locals()['PyFrame_GetCode'] = lambda frame: frame.f_code
+locals()['PyFrame_GetLineNumber'] = lambda frame: frame.f_lineno
 locals()['get_f_back'] = lambda frame: frame.f_back
-locals()['get_f_lineno'] = lambda frame: frame.f_lineno
-locals()['get_f_code'] = lambda frame: frame.f_code
+
 
 if _PYPY:
     import _continuation # pylint:disable=import-error
@@ -158,8 +159,8 @@ def _extract_stack(limit):
         # Arguments are always passed to the constructor as Python objects,
         # meaning we wind up boxing the f_lineno just to unbox it if we pass it.
         # It's faster to simply assign once the object is created.
-        older_Frame.f_code = get_f_code(frame)
-        older_Frame.f_lineno = get_f_lineno(frame) # pylint:disable=undefined-variable
+        older_Frame.f_code = PyFrame_GetCode(frame)  # pylint:disable=undefined-variable
+        older_Frame.f_lineno = PyFrame_GetLineNumber(frame) # pylint:disable=undefined-variable
         if newer_Frame is not None:
             newer_Frame.f_back = older_Frame
         newer_Frame = older_Frame

src/gevent/libev/corecext.pyx

@@ -803,6 +803,7 @@ from gevent._interfaces import ICallback
 classImplements(loop, ILoop)
 classImplements(callback, ICallback)
 
+# XXX: DEF is deprecated. See _setuputils.py for info.
 # about readonly _flags attribute:
 # bit #1 set if object owns Python reference to itself (Py_INCREF was
 # called and we must call Py_DECREF later)

src/gevent/resolver/cares.pyx

@@ -35,6 +35,7 @@ else:
     string_types = __builtins__.basestring,
     text_type = __builtins__.unicode
 
+# XXX: DEF is deprecated. See _setuputils.py for info.
 DEF TIMEOUT = 1
 
 DEF EV_READ = 1

src/gevent/testing/testcase.py

@@ -427,8 +427,13 @@ class TestCase(TestCaseMetaClass("NewBase",
             self.assertEqual(sig.args, gevent_sig.args, func_name)
             # The next three might not actually matter?
             self.assertEqual(sig.varargs, gevent_sig.varargs, func_name)
-            self.assertEqual(sig.keywords, gevent_sig.keywords, func_name)
             self.assertEqual(sig.defaults, gevent_sig.defaults, func_name)
+            if hasattr(sig, 'keywords'): # the old version
+                self.assertEqual(sig.keywords, gevent_sig.keywords, func_name)
+            else:
+                # The new hotness
+                self.assertEqual(sig.kwonlyargs, gevent_sig.kwonlyargs)
+                self.assertEqual(sig.kwonlydefaults, gevent_sig.kwonlydefaults)
             # Should deal with others: https://docs.python.org/3/library/inspect.html#inspect.getfullargspec
 
     def assertEqualFlakyRaceCondition(self, a, b):

tox.ini

 [tox]
 envlist =
-    py27,py36,py37,py38,py39,py310,py27-cffi,pypy,pypy3,py27-libuv,lint
+    py27,py36,py37,py38,py39,py310,py311,py27-cffi,pypy,pypy3,py27-libuv,lint
 
 [testenv]
 usedevelop = true