Expand LIMITED_API support (GH-3311)

* Add more limited api support
* Fix Fused Functions
* Fixed profile
* Use PyModule_GetDict
* Simplify __Pyx_Globals
* Address issues in CommonStructures
* ifdef guard CyFunction and FusedFunction

Cython/Compiler/Code.py

@@ -1078,14 +1078,14 @@ class GlobalState(object):
         'h_code',
         'filename_table',
         'utility_code_proto_before_types',
-        'module_state',
-        'module_state_clear',
-        'module_state_traverse',
-        'module_state_defines',
         'numeric_typedefs',          # Let these detailed individual parts stay!,
         'complex_type_declarations', # as the proper solution is to make a full DAG...
         'type_declarations',         # More coarse-grained blocks would simply hide
         'utility_code_proto',        # the ugliness, not fix it
+        'module_state',
+        'module_state_clear',
+        'module_state_traverse',
+        'module_state_defines',
         'module_declarations',
         'typeinfo',
         'before_global_var',

Cython/Compiler/ModuleNode.py

@@ -1203,6 +1203,18 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
                 module_state_traverse.putln(
                     "Py_VISIT(traverse_module_state->%s);" %
                     entry.type.typeptr_cname)
+                if entry.type.typeobj_cname is not None:
+                    module_state.putln("PyObject *%s;" % entry.type.typeobj_cname)
+                    module_state_defines.putln("#define %s %s->%s" % (
+                        entry.type.typeobj_cname,
+                        Naming.modulestateglobal_cname,
+                        entry.type.typeobj_cname))
+                    module_state_clear.putln(
+                        "Py_CLEAR(clear_module_state->%s);" % (
+                        entry.type.typeobj_cname))
+                    module_state_traverse.putln(
+                        "Py_VISIT(traverse_module_state->%s);" % (
+                        entry.type.typeobj_cname))
         code.putln("#endif")
 
     def generate_cvariable_declarations(self, env, code, definition):
@@ -1365,12 +1377,8 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
         freecount_name = scope.mangle_internal(Naming.freecount_name)
 
         decls = code.globalstate['decls']
-        if cinit_func_entry is None:
-            decls.putln("#if !CYTHON_COMPILING_IN_LIMITED_API")
         decls.putln("static PyObject *%s(PyTypeObject *t, PyObject *a, PyObject *k); /*proto*/" %
                     slot_func)
-        if cinit_func_entry is None:
-            decls.putln("#endif")
         code.putln("")
         if freelist_size:
             code.putln("static %s[%d];" % (
@@ -1378,8 +1386,6 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
                 freelist_size))
             code.putln("static int %s = 0;" % freecount_name)
             code.putln("")
-        if cinit_func_entry is None:
-            code.putln("#if !CYTHON_COMPILING_IN_LIMITED_API")
         code.putln(
             "static PyObject *%s(PyTypeObject *t, %sPyObject *a, %sPyObject *k) {" % (
                 slot_func, unused_marker, unused_marker))
@@ -1390,10 +1396,16 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
         if need_self_cast:
             code.putln("%s;" % scope.parent_type.declaration_code("p"))
         if base_type:
+            code.putln("#if CYTHON_COMPILING_IN_LIMITED_API")
+            code.putln("newfunc new_func = (newfunc)PyType_GetSlot(%s, Py_tp_new);" %
+                base_type.typeptr_cname)
+            code.putln("PyObject *o = new_func(t, a, k);")
+            code.putln("#else")
             tp_new = TypeSlots.get_base_slot_function(scope, tp_slot)
             if tp_new is None:
                 tp_new = "%s->tp_new" % base_type.typeptr_cname
             code.putln("PyObject *o = %s(t, a, k);" % tp_new)
+            code.putln("#endif")
         else:
             code.putln("PyObject *o;")
             code.putln("#if CYTHON_COMPILING_IN_LIMITED_API")
@@ -1425,10 +1437,11 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
                 code.putln("} else {")
                 code.putln("o = (PyObject *) PyBaseObject_Type.tp_new(t, %s, 0);" % Naming.empty_tuple)
                 code.putln("}")
-            code.putln("#endif")
         code.putln("if (unlikely(!o)) return 0;")
         if freelist_size and not base_type:
             code.putln('}')
+        if not base_type:
+            code.putln("#endif")
         if need_self_cast:
             code.putln("p = %s;" % type.cast_code("o"))
         #if need_self_cast:
@@ -1488,8 +1501,6 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
             code.putln("return NULL;")
         code.putln(
             "}")
-        if cinit_func_entry is None:
-            code.putln("#endif")
 
     def generate_dealloc_function(self, scope, code):
         tp_slot = TypeSlots.ConstructorSlot("tp_dealloc", '__dealloc__')
@@ -2234,8 +2245,6 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
         for slot in TypeSlots.slot_table:
             if slot.slot_name == "tp_flags":
                 continue
-            if slot.slot_name == "tp_new" and scope.lookup_here("__cinit__") is None:
-                continue
             if slot.slot_name == "tp_dealloc" and scope.lookup_here("__dealloc__") is None:
                 continue
             if slot.slot_name == "tp_getattro":
@@ -2452,26 +2461,18 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
         code.putln('int %s;' % Naming.lineno_cname)
         code.putln('int %s;' % Naming.clineno_cname)
         code.putln('const char *%s;' % Naming.filename_cname)
+        code.putln('#ifdef __Pyx_CyFunction_USED')
+        code.putln('PyObject *%s;' % Naming.cyfunction_type_cname)
+        code.putln('#endif')
+        code.putln('#ifdef __Pyx_FusedFunction_USED')
+        code.putln('PyObject *%s;' % Naming.fusedfunction_type_cname)
+        code.putln('#endif')
 
     def generate_module_state_end(self, env, modules, globalstate):
         module_state = globalstate['module_state']
         module_state_defines = globalstate['module_state_defines']
         module_state_clear = globalstate['module_state_clear']
         module_state_traverse = globalstate['module_state_traverse']
-        for module in modules:
-            definition = module is env
-            for entry in env.c_class_entries:
-                if definition or entry.defined_in_pxd:
-                    module_state.putln("PyObject *%s;" % entry.type.typeobj_cname)
-                    module_state_defines.putln("#define %s %s->%s" % (
-                        entry.type.typeobj_cname,
-                        Naming.modulestateglobal_cname,
-                        entry.type.typeobj_cname))
-                    module_state_clear.putln("Py_CLEAR(clear_module_state->%s);" %
-                        entry.type.typeobj_cname)
-                    module_state_traverse.putln(
-                        "Py_VISIT(traverse_module_state->%s);" %
-                        entry.type.typeobj_cname)
         module_state.putln('} %s;' % Naming.modulestate_cname)
         module_state.putln('')
         module_state.putln('#ifdef __cplusplus')
@@ -2542,6 +2543,18 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
             Naming.filename_cname,
             Naming.modulestateglobal_cname,
             Naming.filename_cname))
+        code.putln('#ifdef __Pyx_CyFunction_USED')
+        code.putln('#define %s %s->%s' % (
+            Naming.cyfunction_type_cname,
+            Naming.modulestateglobal_cname,
+            Naming.cyfunction_type_cname))
+        code.putln('#endif')
+        code.putln('#ifdef __Pyx_FusedFunction_USED')
+        code.putln('#define %s %s->%s' %
+            (Naming.fusedfunction_type_cname,
+            Naming.modulestateglobal_cname,
+            Naming.fusedfunction_type_cname))
+        code.putln('#endif')
 
     def generate_module_state_clear(self, env, code):
         code.putln("#if CYTHON_COMPILING_IN_LIMITED_API")
@@ -2560,6 +2573,14 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
             Naming.empty_bytes)
         code.putln('Py_CLEAR(clear_module_state->%s);' %
             Naming.empty_unicode)
+        code.putln('#ifdef __Pyx_CyFunction_USED')
+        code.putln('Py_CLEAR(clear_module_state->%s);' %
+            Naming.cyfunction_type_cname)
+        code.putln('#endif')
+        code.putln('#ifdef __Pyx_FusedFunction_USED')
+        code.putln('Py_CLEAR(clear_module_state->%s);' %
+            Naming.fusedfunction_type_cname)
+        code.putln('#endif')
 
     def generate_module_state_traverse(self, env, code):
         code.putln("#if CYTHON_COMPILING_IN_LIMITED_API")
@@ -2578,6 +2599,14 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
             Naming.empty_bytes)
         code.putln('Py_VISIT(traverse_module_state->%s);' %
             Naming.empty_unicode)
+        code.putln('#ifdef __Pyx_CyFunction_USED')
+        code.putln('Py_VISIT(traverse_module_state->%s);' %
+            Naming.cyfunction_type_cname)
+        code.putln('#endif')
+        code.putln('#ifdef __Pyx_FusedFunction_USED')
+        code.putln('Py_VISIT(traverse_module_state->%s);' %
+            Naming.fusedfunction_type_cname)
+        code.putln('#endif')
 
     def generate_module_init_func(self, imported_modules, env, code):
         subfunction = self.mod_init_subfunction(self.scope, code)
@@ -3371,7 +3400,7 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
         if type.vtabptr_cname:
             code.globalstate.use_utility_code(
                 UtilityCode.load_cached('GetVTable', 'ImportExport.c'))
-            code.putln("%s = (struct %s*)__Pyx_GetVtable(%s->tp_dict); %s" % (
+            code.putln("%s = (struct %s*)__Pyx_GetVtable(%s); %s" % (
                 type.vtabptr_cname,
                 type.vtabstruct_cname,
                 type.typeptr_cname,

Cython/Compiler/Naming.py

@@ -134,6 +134,8 @@ tp_dict_version_temp = pyrex_prefix + "tp_dict_version"
 obj_dict_version_temp = pyrex_prefix + "obj_dict_version"
 type_dict_guard_temp = pyrex_prefix + "type_dict_guard"
 cython_runtime_cname   = pyrex_prefix + "cython_runtime"
+cyfunction_type_cname = pyrex_prefix + "CyFunctionType"
+fusedfunction_type_cname = pyrex_prefix + "FusedFunctionType"
 
 global_code_object_cache_find = pyrex_prefix + 'find_code_object'
 global_code_object_cache_insert = pyrex_prefix + 'insert_code_object'

Cython/Compiler/Nodes.py

@@ -5078,11 +5078,29 @@ class CClassDefNode(ClassDefNode):
             return
         if entry.visibility != 'extern':
             code.putln("#if CYTHON_COMPILING_IN_LIMITED_API")
-            code.putln(
-                "%s = PyType_FromSpec(&%s_spec); %s" % (
-                    typeobj_cname,
-                    typeobj_cname,
-                    code.error_goto_if_null(typeobj_cname, entry.pos)))
+            tuple_temp = code.funcstate.allocate_temp(py_object_type, manage_ref=True)
+            base_type = scope.parent_type.base_type
+            if base_type:
+                code.putln(
+                    "%s = PyTuple_Pack(1, (PyObject *)%s); %s" % (
+                    tuple_temp,
+                    base_type.typeptr_cname,
+                    code.error_goto_if_null(tuple_temp, entry.pos)))
+                code.put_gotref(tuple_temp)
+                code.putln(
+                    "%s = PyType_FromSpecWithBases(&%s_spec, %s); %s" % (
+                        typeobj_cname,
+                        typeobj_cname,
+                        tuple_temp,
+                        code.error_goto_if_null(typeobj_cname, entry.pos)))
+                code.put_xdecref_clear(tuple_temp, type=py_object_type)
+                code.funcstate.release_temp(tuple_temp)
+            else:
+                code.putln(
+                    "%s = PyType_FromSpec(&%s_spec); %s" % (
+                        typeobj_cname,
+                        typeobj_cname,
+                        code.error_goto_if_null(typeobj_cname, entry.pos)))
             code.putln("#else")
             for slot in TypeSlots.slot_table:
                 slot.generate_dynamic_init_code(scope, code)
@@ -5227,7 +5245,11 @@ class CClassDefNode(ClassDefNode):
         # Generate code to initialise the typeptr of an extension
         # type defined in this module to point to its type object.
         if type.typeobj_cname:
-            code.putln("#if !CYTHON_COMPILING_IN_LIMITED_API")
+            code.putln("#if CYTHON_COMPILING_IN_LIMITED_API")
+            code.putln(
+                "%s = (PyTypeObject *)%s;" % (
+                    type.typeptr_cname, type.typeobj_cname))
+            code.putln("#else")
             code.putln(
                 "%s = &%s;" % (
                     type.typeptr_cname, type.typeobj_cname))

Cython/Utility/Builtins.c

@@ -20,47 +20,15 @@ static PyObject* __Pyx_Globals(void); /*proto*/
 // access requires a rewrite as a dedicated class.
 
 static PyObject* __Pyx_Globals(void) {
-    Py_ssize_t i;
-    PyObject *names;
-    PyObject *globals = $moddict_cname;
-    Py_INCREF(globals);
-    names = PyObject_Dir($module_cname);
-    if (!names)
-        goto bad;
-    for (i = PyList_GET_SIZE(names)-1; i >= 0; i--) {
-#if CYTHON_COMPILING_IN_PYPY
-        PyObject* name = PySequence_ITEM(names, i);
-        if (!name)
-            goto bad;
+    PyObject *globals;
+#if CYTHON_COMPILING_IN_LIMITED_API
+    globals = PyModule_GetDict($module_cname);
+    if (unlikely(!globals)) return NULL;
 #else
-        PyObject* name = PyList_GET_ITEM(names, i);
-#endif
-        if (!PyDict_Contains(globals, name)) {
-            PyObject* value = __Pyx_GetAttr($module_cname, name);
-            if (!value) {
-#if CYTHON_COMPILING_IN_PYPY
-                Py_DECREF(name);
-#endif
-                goto bad;
-            }
-            if (PyDict_SetItem(globals, name, value) < 0) {
-#if CYTHON_COMPILING_IN_PYPY
-                Py_DECREF(name);
-#endif
-                Py_DECREF(value);
-                goto bad;
-            }
-        }
-#if CYTHON_COMPILING_IN_PYPY
-        Py_DECREF(name);
+    globals = $moddict_cname;
 #endif
-    }
-    Py_DECREF(names);
+    Py_INCREF(globals);
     return globals;
-bad:
-    Py_XDECREF(names);
-    Py_XDECREF(globals);
-    return NULL;
 }
 
 //////////////////// PyExecGlobals.proto ////////////////////

Cython/Utility/CommonStructures.c

 /////////////// FetchCommonType.proto ///////////////
 
 static PyTypeObject* __Pyx_FetchCommonType(PyTypeObject* type);
+#if CYTHON_COMPILING_IN_LIMITED_API
+static PyObject* __Pyx_FetchCommonTypeFromSpec(PyType_Spec *spec, PyObject *bases);
+#endif
 
 /////////////// FetchCommonType ///////////////
 
-static PyTypeObject* __Pyx_FetchCommonType(PyTypeObject* type) {
-    PyObject* fake_module;
-    PyTypeObject* cached_type = NULL;
+static PyObject *__Pyx_FetchSharedCythonABIModule(void) {
+    PyObject *abi_module = PyImport_AddModule((char*) "_cython_" CYTHON_ABI);
+    if (!abi_module) return NULL;
+    Py_INCREF(abi_module);
+    return abi_module;
+}
 
-    fake_module = PyImport_AddModule((char*) "_cython_" CYTHON_ABI);
-    if (!fake_module) return NULL;
-    Py_INCREF(fake_module);
+static int __Pyx_VerifyCachedType(PyObject *cached_type,
+                               const char *name,
+                               Py_ssize_t basicsize,
+                               Py_ssize_t expected_basicsize) {
+    if (!PyType_Check(cached_type)) {
+        PyErr_Format(PyExc_TypeError,
+            "Shared Cython type %.200s is not a type object", name);
+        return -1;
+    }
+    if (basicsize != expected_basicsize) {
+        PyErr_Format(PyExc_TypeError,
+            "Shared Cython type %.200s has the wrong size, try recompiling",
+            name);
+        return -1;
+    }
+    return 0;
+}
+
+static PyTypeObject* __Pyx_FetchCommonType(PyTypeObject* type) {
+    PyObject* abi_module;
+    PyTypeObject *cached_type = NULL;
 
-    cached_type = (PyTypeObject*) PyObject_GetAttrString(fake_module, type->tp_name);
+    abi_module = __Pyx_FetchSharedCythonABIModule();
+    if (!abi_module) return NULL;
+    cached_type = (PyTypeObject*) PyObject_GetAttrString(abi_module, type->tp_name);
     if (cached_type) {
-        if (!PyType_Check((PyObject*)cached_type)) {
-            PyErr_Format(PyExc_TypeError,
-                "Shared Cython type %.200s is not a type object",
-                type->tp_name);
+        if (__Pyx_VerifyCachedType(
+              (PyObject *)cached_type,
+              type->tp_name,
+              cached_type->tp_basicsize,
+              type->tp_basicsize) < 0) {
             goto bad;
         }
-        if (cached_type->tp_basicsize != type->tp_basicsize) {
-            PyErr_Format(PyExc_TypeError,
-                "Shared Cython type %.200s has the wrong size, try recompiling",
-                type->tp_name);
+        goto done;
+    }
+
+    if (!PyErr_ExceptionMatches(PyExc_AttributeError)) goto bad;
+    PyErr_Clear();
+    if (PyType_Ready(type) < 0) goto bad;
+    if (PyObject_SetAttrString(abi_module, type->tp_name, (PyObject *)type) < 0)
+        goto bad;
+    Py_INCREF(type);
+    cached_type = type;
+
+done:
+    Py_DECREF(abi_module);
+    // NOTE: always returns owned reference, or NULL on error
+    return cached_type;
+
+bad:
+    Py_XDECREF(cached_type);
+    cached_type = NULL;
+    goto done;
+}
+
+#if CYTHON_COMPILING_IN_LIMITED_API
+static PyObject *__Pyx_FetchCommonTypeFromSpec(PyType_Spec *spec, PyObject *bases) {
+    PyObject *abi_module, *py_basicsize, *type, *cached_type = NULL;
+    Py_ssize_t basicsize;
+
+    abi_module = __Pyx_FetchSharedCythonABIModule();
+    if (!abi_module) return NULL;
+    cached_type = PyObject_GetAttrString(abi_module, spec->name);
+    if (cached_type) {
+        py_basicsize = PyObject_GetAttrString(cached_type, "__basicsize__");
+        if (!py_basicsize) goto bad;
+        basicsize = PyLong_AsSsize_t(py_basicsize);
+        Py_DECREF(py_basicsize);
+        py_basicsize = 0;
+        if (basicsize == (Py_ssize_t)-1 && PyErr_Occurred()) goto bad;
+        if (__Pyx_VerifyCachedType(
+              cached_type,
+              spec->name,
+              basicsize,
+              spec->basicsize) < 0) {
             goto bad;
         }
-    } else {
-        if (!PyErr_ExceptionMatches(PyExc_AttributeError)) goto bad;
-        PyErr_Clear();
-        if (PyType_Ready(type) < 0) goto bad;
-        if (PyObject_SetAttrString(fake_module, type->tp_name, (PyObject*) type) < 0)
-            goto bad;
-        Py_INCREF(type);
-        cached_type = type;
+        goto done;
     }
 
+    if (!PyErr_ExceptionMatches(PyExc_AttributeError)) goto bad;
+    PyErr_Clear();
+    type = PyType_FromSpecWithBases(spec, bases);
+    if (unlikely(!type)) goto bad;
+    if (PyObject_SetAttrString(abi_module, spec->name, type) < 0) goto bad;
+    cached_type = type;
+
 done:
-    Py_DECREF(fake_module);
+    Py_DECREF(abi_module);
     // NOTE: always returns owned reference, or NULL on error
     return cached_type;
 
@@ -46,6 +111,7 @@ bad:
     cached_type = NULL;
     goto done;
 }
+#endif
 
 
 /////////////// FetchCommonPointer.proto ///////////////
@@ -56,27 +122,27 @@ static void* __Pyx_FetchCommonPointer(void* pointer, const char* name);
 
 
 static void* __Pyx_FetchCommonPointer(void* pointer, const char* name) {
-    PyObject* fake_module = NULL;
+    PyObject* abi_module = NULL;
     PyObject* capsule = NULL;
     void* value = NULL;
 
-    fake_module = PyImport_AddModule((char*) "_cython_" CYTHON_ABI);
-    if (!fake_module) return NULL;
-    Py_INCREF(fake_module);
+    abi_module = PyImport_AddModule((char*) "_cython_" CYTHON_ABI);
+    if (!abi_module) return NULL;
+    Py_INCREF(abi_module);
 
-    capsule = PyObject_GetAttrString(fake_module, name);
+    capsule = PyObject_GetAttrString(abi_module, name);
     if (!capsule) {
         if (!PyErr_ExceptionMatches(PyExc_AttributeError)) goto bad;
         PyErr_Clear();
         capsule = PyCapsule_New(pointer, name, NULL);
         if (!capsule) goto bad;
-        if (PyObject_SetAttrString(fake_module, name, capsule) < 0)
+        if (PyObject_SetAttrString(abi_module, name, capsule) < 0)
             goto bad;
     }
     value = PyCapsule_GetPointer(capsule, name);
 
 bad:
     Py_XDECREF(capsule);
-    Py_DECREF(fake_module);
+    Py_DECREF(abi_module);
     return value;
 }

Cython/Utility/CythonFunction.c

@@ -48,12 +48,14 @@ typedef struct {
     PyObject *func_annotations; /* function annotations dict */
 } __pyx_CyFunctionObject;
 
+#if !CYTHON_COMPILING_IN_LIMITED_API
 static PyTypeObject *__pyx_CyFunctionType = 0;
+#endif
 
 #define __Pyx_CyFunction_Check(obj)  (__Pyx_TypeCheck(obj, __pyx_CyFunctionType))
 
 #define __Pyx_CyFunction_NewEx(ml, flags, qualname, closure, module, globals, code) \
-    __Pyx_CyFunction_New(__pyx_CyFunctionType, ml, flags, qualname, closure, module, globals, code)
+    __Pyx_CyFunction_New((PyTypeObject *)__pyx_CyFunctionType, ml, flags, qualname, closure, module, globals, code)
 
 static PyObject *__Pyx_CyFunction_New(PyTypeObject *type, PyMethodDef *ml,
                                       int flags, PyObject* qualname,
@@ -435,6 +437,14 @@ static PyGetSetDef __pyx_CyFunction_getsets[] = {
 
 static PyMemberDef __pyx_CyFunction_members[] = {
     {(char *) "__module__", T_OBJECT, offsetof(PyCFunctionObject, m_module), PY_WRITE_RESTRICTED, 0},
+#if CYTHON_COMPILING_IN_LIMITED_API
+    {(char *) "__dictoffset__", T_PYSSIZET, offsetof(__pyx_CyFunctionObject, func_dict), READONLY, 0},
+#if PY_VERSION_HEX < 0x030500A0
+    {(char *) "__weaklistoffset__", T_PYSSIZET, offsetof(__pyx_CyFunctionObject, func_weakreflist), READONLY, 0},
+#else
+    {(char *) "__weaklistoffset__", T_PYSSIZET, offsetof(PyCFunctionObject, m_weakreflist), READONLY, 0},
+#endif
+#endif
     {0, 0, 0,  0, 0}
 };
 
@@ -812,6 +822,29 @@ static PyObject * __Pyx_CyFunction_Vectorcall_FASTCALL_KEYWORDS(PyObject *func,
 }
 #endif
 
+#if CYTHON_COMPILING_IN_LIMITED_API
+static PyType_Slot __pyx_CyFunctionType_slots[] = {
+    {Py_tp_dealloc, (void *)__Pyx_CyFunction_dealloc},
+    {Py_tp_repr, (void *)__Pyx_CyFunction_repr},
+    {Py_tp_call, (void *)__Pyx_CyFunction_CallAsMethod},
+    {Py_tp_traverse, (void *)__Pyx_CyFunction_traverse},
+    {Py_tp_clear, (void *)__Pyx_CyFunction_clear},
+    {Py_tp_methods, (void *)__pyx_CyFunction_methods},
+    {Py_tp_members, (void *)__pyx_CyFunction_members},
+    {Py_tp_getset, (void *)__pyx_CyFunction_getsets},
+    {Py_tp_descr_get, (void *)__Pyx_PyMethod_New},
+    {0, 0},
+};
+
+static PyType_Spec __pyx_CyFunctionType_spec = {
+    "cython_function_or_method",
+    sizeof(__pyx_CyFunctionObject),
+    0,
+    // TODO: Support _Py_TPFLAGS_HAVE_VECTORCALL and _Py_TPFLAGS_HAVE_VECTORCALL
+    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC, /*tp_flags*/
+    __pyx_CyFunctionType_slots
+};
+#else
 static PyTypeObject __pyx_CyFunctionType_type = {
     PyVarObject_HEAD_INIT(0, 0)
     "cython_function_or_method",      /*tp_name*/
@@ -890,10 +923,15 @@ static PyTypeObject __pyx_CyFunctionType_type = {
     0,                                  /*tp_print*/
 #endif
 };
+#endif  /* CYTHON_COMPILING_IN_LIMITED_API */
 
 
 static int __pyx_CyFunction_init(void) {
+#if CYTHON_COMPILING_IN_LIMITED_API
+    __pyx_CyFunctionType = __Pyx_FetchCommonTypeFromSpec(&__pyx_CyFunctionType_spec, NULL);
+#else
     __pyx_CyFunctionType = __Pyx_FetchCommonType(&__pyx_CyFunctionType_type);
+#endif
     if (unlikely(__pyx_CyFunctionType == NULL)) {
         return -1;
     }
@@ -965,7 +1003,7 @@ typedef struct {
 } __pyx_FusedFunctionObject;
 
 #define __pyx_FusedFunction_NewEx(ml, flags, qualname, closure, module, globals, code)         \
-        __pyx_FusedFunction_New(__pyx_FusedFunctionType, ml, flags, qualname, closure, module, globals, code)
+        __pyx_FusedFunction_New((PyTypeObject *)__pyx_FusedFunctionType, ml, flags, qualname, closure, module, globals, code)
 static PyObject *__pyx_FusedFunction_New(PyTypeObject *type,
                                          PyMethodDef *ml, int flags,
                                          PyObject *qualname, PyObject *closure,
@@ -973,7 +1011,9 @@ static PyObject *__pyx_FusedFunction_New(PyTypeObject *type,
                                          PyObject *code);
 
 static int __pyx_FusedFunction_clear(__pyx_FusedFunctionObject *self);
+#if !CYTHON_COMPILING_IN_LIMITED_API
 static PyTypeObject *__pyx_FusedFunctionType = NULL;
+#endif
 static int __pyx_FusedFunction_init(void);
 
 #define __Pyx_FusedFunction_USED
@@ -1305,6 +1345,27 @@ static PyMappingMethods __pyx_FusedFunction_mapping_methods = {
     0,
 };
 
+#if CYTHON_COMPILING_IN_LIMITED_API
+static PyType_Slot __pyx_FusedFunctionType_slots[] = {
+    {Py_tp_dealloc, (void *)__pyx_FusedFunction_dealloc},
+    {Py_tp_call, (void *)__pyx_FusedFunction_call},
+    {Py_tp_traverse, (void *)__pyx_FusedFunction_traverse},
+    {Py_tp_clear, (void *)__pyx_FusedFunction_clear},
+    {Py_tp_members, (void *)__pyx_FusedFunction_members},
+    {Py_tp_getset, (void *)__pyx_CyFunction_getsets},
+    {Py_tp_descr_get, (void *)__pyx_FusedFunction_descr_get},
+    {Py_mp_ass_subscript, (void *)__pyx_FusedFunction_getitem},
+    {0, 0},
+};
+
+static PyType_Spec __pyx_FusedFunctionType_spec = {
+    "fused_cython_function",
+    sizeof(__pyx_FusedFunctionObject),
+    0,
+    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC | Py_TPFLAGS_BASETYPE, /*tp_flags*/
+    __pyx_FusedFunctionType_slots
+};
+#else
 static PyTypeObject __pyx_FusedFunctionType_type = {
     PyVarObject_HEAD_INIT(0, 0)
     "fused_cython_function",           /*tp_name*/
@@ -1369,9 +1430,19 @@ static PyTypeObject __pyx_FusedFunctionType_type = {
     0,                                  /*tp_print*/
 #endif
 };
+#endif
 
 static int __pyx_FusedFunction_init(void) {
+#if CYTHON_COMPILING_IN_LIMITED_API
+    PyObject *bases = PyTuple_Pack(1, __pyx_CyFunctionType);
+    if (unlikely(!bases)) {
+        return -1;
+    }
+    __pyx_FusedFunctionType = __Pyx_FetchCommonTypeFromSpec(&__pyx_FusedFunctionType_spec, bases);
+    Py_DECREF(bases);
+#else
     __pyx_FusedFunctionType = __Pyx_FetchCommonType(&__pyx_FusedFunctionType_type);
+#endif
     if (__pyx_FusedFunctionType == NULL) {
         return -1;
     }

Cython/Utility/ImportExport.c

@@ -475,7 +475,7 @@ static PyTypeObject *__Pyx_ImportType(PyObject *module, const char *module_name,
     PyObject *result = 0;
     char warning[200];
     Py_ssize_t basicsize;
-#ifdef Py_LIMITED_API
+#if CYTHON_COMPILING_IN_LIMITED_API
     PyObject *py_basicsize;
 #endif
 
@@ -488,7 +488,7 @@ static PyTypeObject *__Pyx_ImportType(PyObject *module, const char *module_name,
             module_name, class_name);
         goto bad;
     }
-#ifndef Py_LIMITED_API
+#if !CYTHON_COMPILING_IN_LIMITED_API
     basicsize = ((PyTypeObject *)result)->tp_basicsize;
 #else
     py_basicsize = PyObject_GetAttrString(result, "__basicsize__");
@@ -720,13 +720,17 @@ bad:
 
 /////////////// GetVTable.proto ///////////////
 
-static void* __Pyx_GetVtable(PyObject *dict); /*proto*/
+static void* __Pyx_GetVtable(PyTypeObject *type); /*proto*/
 
 /////////////// GetVTable ///////////////
 
-static void* __Pyx_GetVtable(PyObject *dict) {
+static void* __Pyx_GetVtable(PyTypeObject *type) {
     void* ptr;
-    PyObject *ob = PyObject_GetItem(dict, PYIDENT("__pyx_vtable__"));
+#if CYTHON_COMPILING_IN_LIMITED_API
+    PyObject *ob = PyObject_GetAttr((PyObject *)type, PYIDENT("__pyx_vtable__"));
+#else
+    PyObject *ob = PyObject_GetItem(type->tp_dict, PYIDENT("__pyx_vtable__"));
+#endif
     if (!ob)
         goto bad;
     ptr = PyCapsule_GetPointer(ob, 0);
@@ -769,13 +773,13 @@ static int __Pyx_MergeVtables(PyTypeObject *type) {
     // instance struct is so extended.  (It would be good to also do this
     // check when a multiple-base class is created in pure Python as well.)
     for (i = 1; i < PyTuple_GET_SIZE(bases); i++) {
-        void* base_vtable = __Pyx_GetVtable(((PyTypeObject*)PyTuple_GET_ITEM(bases, i))->tp_dict);
+        void* base_vtable = __Pyx_GetVtable(((PyTypeObject*)PyTuple_GET_ITEM(bases, i)));
         if (base_vtable != NULL) {
             int j;
             PyTypeObject* base = type->tp_base;
             for (j = 0; j < base_depth; j++) {
                 if (base_vtables[j] == unknown) {
-                    base_vtables[j] = __Pyx_GetVtable(base->tp_dict);
+                    base_vtables[j] = __Pyx_GetVtable(base);
                     base_vtables[j + 1] = unknown;
                 }
                 if (base_vtables[j] == base_vtable) {

Cython/Utility/ObjectHandling.c

@@ -1293,7 +1293,7 @@ static CYTHON_INLINE PyObject *__Pyx__GetModuleGlobalName(PyObject *name)
     if (unlikely(!$module_cname)) {
         return NULL;
     }
-    result = PyObject_GetItem($module_cname, name);
+    result = PyObject_GetAttr($module_cname, name);
     if (likely(result)) {
         return result;
     }

Cython/Utility/Profile.c

@@ -6,7 +6,7 @@
 // but maybe some other profilers don't.
 
 #ifndef CYTHON_PROFILE
-#if CYTHON_COMPILING_IN_PYPY || CYTHON_COMPILING_IN_PYSTON
+#if CYTHON_COMPILING_IN_LIMITED_API || CYTHON_COMPILING_IN_PYPY || CYTHON_COMPILING_IN_PYSTON
   #define CYTHON_PROFILE 0
 #else
   #define CYTHON_PROFILE 1

runtests.py

@@ -2372,6 +2372,7 @@ def runtests(options, cmd_args, coverage=None):
 
     if options.limited_api:
         CFLAGS.append("-DCYTHON_LIMITED_API=1")
+        CFLAGS.append('-Wno-unused-function')
 
 
     if xml_output_dir and options.fork:

tests/limited_api_bugs.txt

 # This file contains tests corresponding to unresolved bugs using CPython's
 # Limited API which will be skipped in the normal testing run.
 
-calc_pi_2
-calc_pi_3
-calc_pi_4
-clone
 convolve2
-cpdef_sin
 dict_animal
-integrate
-landscaping
-mymodule
 not_none
-overhead
-profile
-profile_2
 queue3
-resize
-safe_usage
-shrubbery_2
-sin_of_square
 test_queue
-unsafe_usage
-wave_function