diff --git a/noxfile.py b/noxfile.py
index d16227c36ec..8ab8d9ec545 100644
--- a/noxfile.py
+++ b/noxfile.py
@@ -499,6 +499,7 @@ def set_minimal_package_versions(session: nox.Session):
         "trybuild": "1.0.76",
         # pins to avoid syn 2.0 (which requires Rust 1.56)
         "ghost": "0.1.8",
+        "serde_json": "1.0.99",
         "serde": "1.0.156",
         "serde_derive": "1.0.156",
         "cxx": "1.0.92",
@@ -508,6 +509,9 @@ def set_minimal_package_versions(session: nox.Session):
         "js-sys": "0.3.61",
         "wasm-bindgen": "0.2.84",
         "syn": "1.0.109",
+        # proc-macro2 1.0.66+ is edition 2021
+        "quote": "1.0.30",
+        "proc-macro2": "1.0.65",
     }
     # run cargo update first to ensure that everything is at highest
     # possible version, so that this matches what CI will resolve to.
diff --git a/pyo3-ffi/src/cpython/abstract_.rs b/pyo3-ffi/src/cpython/abstract_.rs
index dd029f3324a..d2e3ca9d67a 100644
--- a/pyo3-ffi/src/cpython/abstract_.rs
+++ b/pyo3-ffi/src/cpython/abstract_.rs
@@ -41,11 +41,11 @@ extern "C" {
     ) -> *mut PyObject;
 }
 
-#[cfg(all(Py_3_8))]
+#[cfg(Py_3_8)]
 const PY_VECTORCALL_ARGUMENTS_OFFSET: Py_ssize_t =
     1 << (8 * std::mem::size_of::<Py_ssize_t>() as Py_ssize_t - 1);
 
-#[cfg(all(Py_3_8))]
+#[cfg(Py_3_8)]
 #[inline(always)]
 pub unsafe fn PyVectorcall_NARGS(n: size_t) -> Py_ssize_t {
     assert!(n <= (PY_SSIZE_T_MAX as size_t));
@@ -113,7 +113,7 @@ extern "C" {
         kwnames: *mut PyObject,
     ) -> *mut PyObject;
 
-    #[cfg(all(Py_3_8))]
+    #[cfg(Py_3_8)]
     #[cfg_attr(all(not(PyPy), not(Py_3_9)), link_name = "_PyObject_VectorcallDict")]
     #[cfg_attr(all(PyPy, not(Py_3_9)), link_name = "_PyPyObject_VectorcallDict")]
     #[cfg_attr(all(PyPy, Py_3_9), link_name = "PyPyObject_VectorcallDict")]
@@ -124,7 +124,7 @@ extern "C" {
         kwdict: *mut PyObject,
     ) -> *mut PyObject;
 
-    #[cfg(all(Py_3_8))]
+    #[cfg(Py_3_8)]
     #[cfg_attr(not(any(Py_3_9, PyPy)), link_name = "_PyVectorcall_Call")]
     #[cfg_attr(PyPy, link_name = "PyPyVectorcall_Call")]
     pub fn PyVectorcall_Call(
diff --git a/pyo3-ffi/src/object.rs b/pyo3-ffi/src/object.rs
index 6ff8beb5a9e..4c53dc7a441 100644
--- a/pyo3-ffi/src/object.rs
+++ b/pyo3-ffi/src/object.rs
@@ -111,8 +111,8 @@ pub unsafe fn Py_TYPE(ob: *mut PyObject) -> *mut PyTypeObject {
 
 #[inline]
 pub unsafe fn Py_SIZE(ob: *mut PyObject) -> Py_ssize_t {
-    debug_assert_ne!((*ob).ob_type, std::ptr::addr_of_mut!(crate::PyLong_Type));
-    debug_assert_ne!((*ob).ob_type, std::ptr::addr_of_mut!(crate::PyBool_Type));
+    debug_assert_ne!((*ob).ob_type, addr_of_mut_shim!(crate::PyLong_Type));
+    debug_assert_ne!((*ob).ob_type, addr_of_mut_shim!(crate::PyBool_Type));
     (*ob.cast::<PyVarObject>()).ob_size
 }
 
diff --git a/pyo3-macros-backend/src/method.rs b/pyo3-macros-backend/src/method.rs
index b290fd55c13..2e2f75d18af 100644
--- a/pyo3-macros-backend/src/method.rs
+++ b/pyo3-macros-backend/src/method.rs
@@ -254,8 +254,8 @@ pub fn parse_method_receiver(arg: &syn::FnArg) -> Result<SelfType> {
         ) => {
             bail_spanned!(recv.span() => RECEIVER_BY_VALUE_ERR);
         }
-        syn::FnArg::Receiver(recv @ syn::Receiver { mutability, .. }) => Ok(SelfType::Receiver {
-            mutable: mutability.is_some(),
+        syn::FnArg::Receiver(recv) => Ok(SelfType::Receiver {
+            mutable: recv.mutability.is_some(),
             span: recv.span(),
         }),
         syn::FnArg::Typed(syn::PatType { ty, .. }) => {
diff --git a/pytests/src/pyclasses.rs b/pytests/src/pyclasses.rs
index 3ee61b343b0..b9c7a5beb48 100644
--- a/pytests/src/pyclasses.rs
+++ b/pytests/src/pyclasses.rs
@@ -16,6 +16,7 @@ impl EmptyClass {
 
 /// This is for demonstrating how to return a value from __next__
 #[pyclass]
+#[derive(Default)]
 struct PyClassIter {
     count: usize,
 }
diff --git a/src/test_hygiene/pyclass.rs b/src/test_hygiene/pyclass.rs
index 0b535abe860..4d07009cad6 100644
--- a/src/test_hygiene/pyclass.rs
+++ b/src/test_hygiene/pyclass.rs
@@ -56,6 +56,6 @@ pub struct Foo4 {
     field: i32,
 
     #[pyo3(get, set)]
-    #[cfg(any(not(FALSE)))]
+    #[cfg(not(FALSE))]
     field: u32,
 }