diff --git a/pyo3-macros-backend/src/module.rs b/pyo3-macros-backend/src/module.rs
index b652f32417d..148cea6f8dd 100644
--- a/pyo3-macros-backend/src/module.rs
+++ b/pyo3-macros-backend/src/module.rs
@@ -211,6 +211,7 @@ pub fn pymodule_function_impl(mut function: syn::ItemFn) -> Result<TokenStream>
         // this avoids complications around the fact that the generated module has a different scope
         // (and `super` doesn't always refer to the outer scope, e.g. if the `#[pymodule] is
         // inside a function body)
+        // FIXME https://github.com/PyO3/pyo3/issues/3903
         #[allow(unknown_lints, non_local_definitions)]
         const _: () = {
             use #krate::impl_::pymodule as impl_;
diff --git a/pyo3-macros-backend/src/pyclass.rs b/pyo3-macros-backend/src/pyclass.rs
index 78dfe7acb7b..1547e78b4c2 100644
--- a/pyo3-macros-backend/src/pyclass.rs
+++ b/pyo3-macros-backend/src/pyclass.rs
@@ -362,6 +362,7 @@ fn impl_class(
     .impl_all()?;
 
     Ok(quote! {
+        // FIXME https://github.com/PyO3/pyo3/issues/3903
         #[allow(unknown_lints, non_local_definitions)]
         const _: () = {
             use #krate as _pyo3;
@@ -784,6 +785,7 @@ fn impl_simple_enum(
     .impl_all()?;
 
     Ok(quote! {
+        // FIXME https://github.com/PyO3/pyo3/issues/3903
         #[allow(unknown_lints, non_local_definitions)]
         const _: () = {
             use #krate as _pyo3;
@@ -919,6 +921,7 @@ fn impl_complex_enum(
     }
 
     Ok(quote! {
+        // FIXME https://github.com/PyO3/pyo3/issues/3903
         #[allow(unknown_lints, non_local_definitions)]
         const _: () = {
             use #krate as _pyo3;
diff --git a/pyo3-macros-backend/src/pyfunction.rs b/pyo3-macros-backend/src/pyfunction.rs
index 2f50c76a654..38362d08a00 100644
--- a/pyo3-macros-backend/src/pyfunction.rs
+++ b/pyo3-macros-backend/src/pyfunction.rs
@@ -281,6 +281,7 @@ pub fn impl_wrap_pyfunction(
         // this avoids complications around the fact that the generated module has a different scope
         // (and `super` doesn't always refer to the outer scope, e.g. if the `#[pyfunction] is
         // inside a function body)
+        // FIXME https://github.com/PyO3/pyo3/issues/3903
         #[allow(unknown_lints, non_local_definitions)]
         const _: () = {
             use #krate as _pyo3;
diff --git a/pyo3-macros-backend/src/pyimpl.rs b/pyo3-macros-backend/src/pyimpl.rs
index a8150a3dba4..5802638e340 100644
--- a/pyo3-macros-backend/src/pyimpl.rs
+++ b/pyo3-macros-backend/src/pyimpl.rs
@@ -168,6 +168,7 @@ pub fn impl_methods(
     };
 
     Ok(quote! {
+        // FIXME https://github.com/PyO3/pyo3/issues/3903
         #[allow(unknown_lints, non_local_definitions)]
         const _: () = {
             use #krate as _pyo3;
diff --git a/src/exceptions.rs b/src/exceptions.rs
index 4999e30c816..071470160ae 100644
--- a/src/exceptions.rs
+++ b/src/exceptions.rs
@@ -19,6 +19,7 @@ use std::os::raw::c_char;
 #[macro_export]
 macro_rules! impl_exception_boilerplate {
     ($name: ident) => {
+        // FIXME https://github.com/PyO3/pyo3/issues/3903
         #[allow(unknown_lints, non_local_definitions)]
         impl ::std::convert::From<&$name> for $crate::PyErr {
             #[inline]
diff --git a/src/types/mod.rs b/src/types/mod.rs
index c00cf610d18..938716f78f4 100644
--- a/src/types/mod.rs
+++ b/src/types/mod.rs
@@ -188,6 +188,7 @@ macro_rules! pyobject_native_type_named (
             }
         }
 
+        // FIXME https://github.com/PyO3/pyo3/issues/3903
         #[allow(unknown_lints, non_local_definitions)]
         impl<$($generics,)*> $crate::IntoPy<$crate::Py<$name>> for &'_ $name {
             #[inline]
@@ -196,6 +197,7 @@ macro_rules! pyobject_native_type_named (
             }
         }
 
+        // FIXME https://github.com/PyO3/pyo3/issues/3903
         #[allow(unknown_lints, non_local_definitions)]
         impl<$($generics,)*> ::std::convert::From<&'_ $name> for $crate::Py<$name> {
             #[inline]
@@ -205,6 +207,7 @@ macro_rules! pyobject_native_type_named (
             }
         }
 
+        // FIXME https://github.com/PyO3/pyo3/issues/3903
         #[allow(unknown_lints, non_local_definitions)]
         impl<'a, $($generics,)*> ::std::convert::From<&'a $name> for &'a $crate::PyAny {
             fn from(ob: &'a $name) -> Self {
@@ -255,6 +258,7 @@ macro_rules! pyobject_native_type_info(
 #[macro_export]
 macro_rules! pyobject_native_type_extract {
     ($name:ty $(;$generics:ident)*) => {
+        // FIXME https://github.com/PyO3/pyo3/issues/3903
         #[allow(unknown_lints, non_local_definitions)]
         impl<'py, $($generics,)*> $crate::FromPyObject<'py> for &'py $name {
             #[inline]