diff --git a/src/ffi/setobject.rs b/src/ffi/setobject.rs
index cd837b9b..b71c275b 100644
--- a/src/ffi/setobject.rs
+++ b/src/ffi/setobject.rs
@@ -1,30 +1,12 @@
 use crate::ffi::object::*;
-use crate::ffi::pyport::{Py_hash_t, Py_ssize_t};
+#[cfg(not(Py_LIMITED_API))]
+use crate::ffi::pyport::Py_hash_t;
+use crate::ffi::pyport::Py_ssize_t;
 use std::os::raw::c_int;
 
-#[cfg_attr(windows, link(name = "pythonXY"))]
-extern "C" {
-    #[cfg_attr(PyPy, link_name = "PyPySet_Type")]
-    pub static mut PySet_Type: PyTypeObject;
-    #[cfg_attr(PyPy, link_name = "PyPyFrozenSet_Type")]
-    pub static mut PyFrozenSet_Type: PyTypeObject;
-    pub static mut PySetIter_Type: PyTypeObject;
-
-    #[cfg(PyPy)]
-    #[link_name = "PyPyFrozenSet_CheckExact"]
-    pub fn PyFrozenSet_CheckExact(ob: *mut PyObject) -> c_int;
-
-    #[cfg(PyPy)]
-    #[link_name = "PyPyAnySet_CheckExact"]
-    pub fn PyAnySet_CheckExact(ob: *mut PyObject) -> c_int;
-
-    #[cfg(PyPy)]
-    #[link_name = "PyPySet_Check"]
-    pub fn PySet_Check(ob: *mut PyObject) -> c_int;
-}
-
 pub const PySet_MINSIZE: usize = 8;
 
+#[cfg(not(Py_LIMITED_API))]
 #[repr(C)]
 #[derive(Debug)]
 pub struct setentry {
@@ -32,6 +14,7 @@ pub struct setentry {
     pub hash: Py_hash_t,
 }
 
+#[cfg(not(Py_LIMITED_API))]
 #[repr(C)]
 #[derive(Debug)]
 pub struct PySetObject {
@@ -46,12 +29,81 @@ pub struct PySetObject {
     pub weakreflist: *mut PyObject,
 }
 
+// skipped PySet_GET_SIZE
+
+// skipped _PySet_Dummy
+
+extern "C" {
+    #[cfg(not(Py_LIMITED_API))]
+    #[cfg_attr(PyPy, link_name = "_PyPySet_NextEntry")]
+    pub fn _PySet_NextEntry(
+        set: *mut PyObject,
+        pos: *mut Py_ssize_t,
+        key: *mut *mut PyObject,
+        hash: *mut super::Py_hash_t,
+    ) -> c_int;
+
+    // skipped non-limited _PySet_Update
+}
+
+#[cfg_attr(windows, link(name = "pythonXY"))]
+extern "C" {
+    #[cfg_attr(PyPy, link_name = "PyPySet_Type")]
+    pub static mut PySet_Type: PyTypeObject;
+    #[cfg_attr(PyPy, link_name = "PyPyFrozenSet_Type")]
+    pub static mut PyFrozenSet_Type: PyTypeObject;
+    pub static mut PySetIter_Type: PyTypeObject;
+}
+
+extern "C" {
+    #[cfg_attr(PyPy, link_name = "PyPySet_New")]
+    pub fn PySet_New(arg1: *mut PyObject) -> *mut PyObject;
+    #[cfg_attr(PyPy, link_name = "PyPyFrozenSet_New")]
+    pub fn PyFrozenSet_New(arg1: *mut PyObject) -> *mut PyObject;
+
+    #[cfg_attr(PyPy, link_name = "PyPySet_Add")]
+    pub fn PySet_Add(set: *mut PyObject, key: *mut PyObject) -> c_int;
+    #[cfg_attr(PyPy, link_name = "PyPySet_Clear")]
+    pub fn PySet_Clear(set: *mut PyObject) -> c_int;
+    #[cfg_attr(PyPy, link_name = "PyPySet_Contains")]
+    pub fn PySet_Contains(anyset: *mut PyObject, key: *mut PyObject) -> c_int;
+    #[cfg_attr(PyPy, link_name = "PyPySet_Discard")]
+    pub fn PySet_Discard(set: *mut PyObject, key: *mut PyObject) -> c_int;
+    #[cfg_attr(PyPy, link_name = "PyPySet_Pop")]
+    pub fn PySet_Pop(set: *mut PyObject) -> *mut PyObject;
+    #[cfg_attr(PyPy, link_name = "PyPySet_Size")]
+    pub fn PySet_Size(anyset: *mut PyObject) -> Py_ssize_t;
+
+    #[cfg(PyPy)]
+    #[link_name = "PyPyFrozenSet_CheckExact"]
+    pub fn PyFrozenSet_CheckExact(ob: *mut PyObject) -> c_int;
+}
+
 #[inline]
 #[cfg(not(PyPy))]
 pub unsafe fn PyFrozenSet_CheckExact(ob: *mut PyObject) -> c_int {
     (Py_TYPE(ob) == &mut PyFrozenSet_Type) as c_int
 }
 
+extern "C" {
+    #[cfg(PyPy)]
+    #[link_name = "PyPyFrozenSet_Check"]
+    pub fn PyFrozenSet_Check(ob: *mut PyObject) -> c_int;
+}
+
+#[inline]
+#[cfg(not(PyPy))]
+pub unsafe fn PyFrozenSet_Check(ob: *mut PyObject) -> c_int {
+    (Py_TYPE(ob) == &mut PyFrozenSet_Type
+        || PyType_IsSubtype(Py_TYPE(ob), &mut PyFrozenSet_Type) != 0) as c_int
+}
+
+extern "C" {
+    #[cfg(PyPy)]
+    #[link_name = "PyPyAnySet_CheckExact"]
+    pub fn PyAnySet_CheckExact(ob: *mut PyObject) -> c_int;
+}
+
 #[inline]
 #[cfg(not(PyPy))]
 pub unsafe fn PyAnySet_CheckExact(ob: *mut PyObject) -> c_int {
@@ -65,42 +117,16 @@ pub unsafe fn PyAnySet_Check(ob: *mut PyObject) -> c_int {
         || PyType_IsSubtype(Py_TYPE(ob), &mut PyFrozenSet_Type) != 0) as c_int
 }
 
+// skipped PySet_CheckExact
+
+extern "C" {
+    #[cfg(PyPy)]
+    #[link_name = "PyPySet_Check"]
+    pub fn PySet_Check(ob: *mut PyObject) -> c_int;
+}
+
 #[inline]
 #[cfg(not(PyPy))]
 pub unsafe fn PySet_Check(ob: *mut PyObject) -> c_int {
     (Py_TYPE(ob) == &mut PySet_Type || PyType_IsSubtype(Py_TYPE(ob), &mut PySet_Type) != 0) as c_int
 }
-
-#[inline]
-pub unsafe fn PyFrozenSet_Check(ob: *mut PyObject) -> c_int {
-    (Py_TYPE(ob) == &mut PyFrozenSet_Type
-        || PyType_IsSubtype(Py_TYPE(ob), &mut PyFrozenSet_Type) != 0) as c_int
-}
-
-extern "C" {
-    #[cfg_attr(PyPy, link_name = "PyPySet_New")]
-    pub fn PySet_New(arg1: *mut PyObject) -> *mut PyObject;
-    #[cfg_attr(PyPy, link_name = "PyPyFrozenSet_New")]
-    pub fn PyFrozenSet_New(arg1: *mut PyObject) -> *mut PyObject;
-    #[cfg_attr(PyPy, link_name = "PyPySet_Size")]
-    pub fn PySet_Size(anyset: *mut PyObject) -> Py_ssize_t;
-    #[cfg_attr(PyPy, link_name = "PyPySet_Clear")]
-    pub fn PySet_Clear(set: *mut PyObject) -> c_int;
-    #[cfg_attr(PyPy, link_name = "PyPySet_Contains")]
-    pub fn PySet_Contains(anyset: *mut PyObject, key: *mut PyObject) -> c_int;
-    #[cfg_attr(PyPy, link_name = "PyPySet_Discard")]
-    pub fn PySet_Discard(set: *mut PyObject, key: *mut PyObject) -> c_int;
-    #[cfg_attr(PyPy, link_name = "PyPySet_Add")]
-    pub fn PySet_Add(set: *mut PyObject, key: *mut PyObject) -> c_int;
-    #[cfg_attr(PyPy, link_name = "PyPySet_Pop")]
-    pub fn PySet_Pop(set: *mut PyObject) -> *mut PyObject;
-
-    #[cfg(not(Py_LIMITED_API))]
-    #[cfg_attr(PyPy, link_name = "_PyPySet_NextEntry")]
-    pub fn _PySet_NextEntry(
-        set: *mut PyObject,
-        pos: *mut Py_ssize_t,
-        key: *mut *mut PyObject,
-        hash: *mut super::Py_hash_t,
-    ) -> c_int;
-}