diff --git a/examples/enum-default-expanded.rs b/examples/enum-default-expanded.rs
index 36baf8ae..02b64f00 100644
--- a/examples/enum-default-expanded.rs
+++ b/examples/enum-default-expanded.rs
@@ -77,13 +77,15 @@ const _: () = {
         __field0: T,
     }
     impl<'pin, T, U> ::pin_project::__private::Unpin for Enum<T, U> where
-        __Enum<'pin, T, U>: ::pin_project::__private::Unpin
+        ::pin_project::__private::PinnedFieldsOf<__Enum<'pin, T, U>>:
+            ::pin_project::__private::Unpin
     {
     }
     // A dummy impl of `UnsafeUnpin`, to ensure that the user cannot implement it.
     #[doc(hidden)]
     unsafe impl<'pin, T, U> ::pin_project::UnsafeUnpin for Enum<T, U> where
-        __Enum<'pin, T, U>: ::pin_project::__private::Unpin
+        ::pin_project::__private::PinnedFieldsOf<__Enum<'pin, T, U>>:
+            ::pin_project::__private::Unpin
     {
     }
 
diff --git a/examples/not_unpin-expanded.rs b/examples/not_unpin-expanded.rs
index 2cdfaab6..c06c9c01 100644
--- a/examples/not_unpin-expanded.rs
+++ b/examples/not_unpin-expanded.rs
@@ -95,9 +95,11 @@ const _: () = {
     //
     // See https://github.com/taiki-e/pin-project/issues/102#issuecomment-540472282
     // for details.
+    #[doc(hidden)]
     impl<'pin, T, U> ::pin_project::__private::Unpin for Struct<T, U> where
-        ::pin_project::__private::Wrapper<'pin, ::pin_project::__private::PhantomPinned>:
-            ::pin_project::__private::Unpin
+        ::pin_project::__private::PinnedFieldsOf<
+            ::pin_project::__private::Wrapper<'pin, ::pin_project::__private::PhantomPinned>,
+        >: ::pin_project::__private::Unpin
     {
     }
     // A dummy impl of `UnsafeUnpin`, to ensure that the user cannot implement it.
@@ -108,8 +110,9 @@ const _: () = {
     // coherence checks are run.
     #[doc(hidden)]
     unsafe impl<'pin, T, U> ::pin_project::UnsafeUnpin for Struct<T, U> where
-        ::pin_project::__private::Wrapper<'pin, ::pin_project::__private::PhantomPinned>:
-            ::pin_project::__private::Unpin
+        ::pin_project::__private::PinnedFieldsOf<
+            ::pin_project::__private::Wrapper<'pin, ::pin_project::__private::PhantomPinned>,
+        >: ::pin_project::__private::Unpin
     {
     }
 
diff --git a/examples/pinned_drop-expanded.rs b/examples/pinned_drop-expanded.rs
index 944769f3..5263de69 100644
--- a/examples/pinned_drop-expanded.rs
+++ b/examples/pinned_drop-expanded.rs
@@ -123,13 +123,15 @@ const _: () = {
         __lifetime0: &'a (),
     }
     impl<'pin, 'a, T> ::pin_project::__private::Unpin for Struct<'a, T> where
-        __Struct<'pin, 'a, T>: ::pin_project::__private::Unpin
+        ::pin_project::__private::PinnedFieldsOf<__Struct<'pin, 'a, T>>:
+            ::pin_project::__private::Unpin
     {
     }
     // A dummy impl of `UnsafeUnpin`, to ensure that the user cannot implement it.
     #[doc(hidden)]
     unsafe impl<'pin, 'a, T> ::pin_project::UnsafeUnpin for Struct<'a, T> where
-        __Struct<'pin, 'a, T>: ::pin_project::__private::Unpin
+        ::pin_project::__private::PinnedFieldsOf<__Struct<'pin, 'a, T>>:
+            ::pin_project::__private::Unpin
     {
     }
 };
diff --git a/examples/project_replace-expanded.rs b/examples/project_replace-expanded.rs
index 5d0d81d5..ffcf8189 100644
--- a/examples/project_replace-expanded.rs
+++ b/examples/project_replace-expanded.rs
@@ -137,13 +137,15 @@ const _: () = {
         __field0: T,
     }
     impl<'pin, T, U> ::pin_project::__private::Unpin for Struct<T, U> where
-        __Struct<'pin, T, U>: ::pin_project::__private::Unpin
+        ::pin_project::__private::PinnedFieldsOf<__Struct<'pin, T, U>>:
+            ::pin_project::__private::Unpin
     {
     }
     // A dummy impl of `UnsafeUnpin`, to ensure that the user cannot implement it.
     #[doc(hidden)]
     unsafe impl<'pin, T, U> ::pin_project::UnsafeUnpin for Struct<T, U> where
-        __Struct<'pin, T, U>: ::pin_project::__private::Unpin
+        ::pin_project::__private::PinnedFieldsOf<__Struct<'pin, T, U>>:
+            ::pin_project::__private::Unpin
     {
     }
 
diff --git a/examples/struct-default-expanded.rs b/examples/struct-default-expanded.rs
index a7ad8c9a..01f2f7e7 100644
--- a/examples/struct-default-expanded.rs
+++ b/examples/struct-default-expanded.rs
@@ -129,7 +129,8 @@ const _: () = {
         __field0: T,
     }
     impl<'pin, T, U> ::pin_project::__private::Unpin for Struct<T, U> where
-        __Struct<'pin, T, U>: ::pin_project::__private::Unpin
+        ::pin_project::__private::PinnedFieldsOf<__Struct<'pin, T, U>>:
+            ::pin_project::__private::Unpin
     {
     }
     // A dummy impl of `UnsafeUnpin`, to ensure that the user cannot implement it.
@@ -140,7 +141,8 @@ const _: () = {
     // coherence checks are run.
     #[doc(hidden)]
     unsafe impl<'pin, T, U> ::pin_project::UnsafeUnpin for Struct<T, U> where
-        __Struct<'pin, T, U>: ::pin_project::__private::Unpin
+        ::pin_project::__private::PinnedFieldsOf<__Struct<'pin, T, U>>:
+            ::pin_project::__private::Unpin
     {
     }
 
diff --git a/examples/unsafe_unpin-expanded.rs b/examples/unsafe_unpin-expanded.rs
index 5627ce83..f4521fcf 100644
--- a/examples/unsafe_unpin-expanded.rs
+++ b/examples/unsafe_unpin-expanded.rs
@@ -92,7 +92,8 @@ const _: () = {
 
     // Implement `Unpin` via `UnsafeUnpin`.
     impl<'pin, T, U> ::pin_project::__private::Unpin for Struct<T, U> where
-        ::pin_project::__private::Wrapper<'pin, Self>: ::pin_project::UnsafeUnpin
+        ::pin_project::__private::PinnedFieldsOf<::pin_project::__private::Wrapper<'pin, Self>>:
+            ::pin_project::UnsafeUnpin
     {
     }
 
diff --git a/pin-project-internal/src/pin_project/derive.rs b/pin-project-internal/src/pin_project/derive.rs
index 60deebf6..c717dffa 100644
--- a/pin-project-internal/src/pin_project/derive.rs
+++ b/pin-project-internal/src/pin_project/derive.rs
@@ -693,7 +693,9 @@ fn make_unpin_impl(cx: &Context<'_>) -> TokenStream {
 
             // Make the error message highlight `UnsafeUnpin` argument.
             proj_generics.make_where_clause().predicates.push(parse_quote_spanned! { span =>
-                _pin_project::__private::Wrapper<#lifetime, Self>: _pin_project::UnsafeUnpin
+                ::pin_project::__private::PinnedFieldsOf<
+                    _pin_project::__private::Wrapper<#lifetime, Self>
+                >: _pin_project::UnsafeUnpin
             });
 
             let (impl_generics, _, where_clause) = proj_generics.split_for_impl();
@@ -712,9 +714,9 @@ fn make_unpin_impl(cx: &Context<'_>) -> TokenStream {
             let lifetime = &cx.proj.lifetime;
 
             proj_generics.make_where_clause().predicates.push(parse_quote! {
-                _pin_project::__private::Wrapper<
+                ::pin_project::__private::PinnedFieldsOf<_pin_project::__private::Wrapper<
                     #lifetime, _pin_project::__private::PhantomPinned
-                >: _pin_project::__private::Unpin
+                >>: _pin_project::__private::Unpin
             });
 
             let (proj_impl_generics, _, proj_where_clause) = proj_generics.split_for_impl();
@@ -793,7 +795,8 @@ fn make_unpin_impl(cx: &Context<'_>) -> TokenStream {
             let (_, ty_generics, where_clause) = cx.orig.generics.split_for_impl();
 
             full_where_clause.predicates.push(parse_quote! {
-                #struct_ident #proj_ty_generics: _pin_project::__private::Unpin
+                ::pin_project::__private::PinnedFieldsOf<#struct_ident #proj_ty_generics>:
+                    _pin_project::__private::Unpin
             });
 
             quote! {
diff --git a/src/lib.rs b/src/lib.rs
index 6ba7c80d..56a661a3 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -276,29 +276,42 @@ pub mod __private {
     #[doc(hidden)]
     #[allow(dead_code)]
     pub struct Wrapper<'a, T: ?Sized>(PhantomData<&'a ()>, T);
-
     // SAFETY: `T` implements UnsafeUnpin.
     unsafe impl<T: ?Sized + UnsafeUnpin> UnsafeUnpin for Wrapper<'_, T> {}
 
+    // Workaround for issue on unstable negative_impls feature that allows unsound overlapping Unpin
+    // implementations and rustc bug that leaks unstable negative_impls into stable.
+    // See https://github.com/taiki-e/pin-project/issues/340#issuecomment-2432146009 for details.
+    #[doc(hidden)]
+    pub type PinnedFieldsOf<T> =
+        <PinnedFieldsOfHelperStruct<T> as PinnedFieldsOfHelperTrait>::Actual;
+    // We cannot use <Option<T> as IntoIterator>::Item or similar since we should allow ?Sized in T.
+    #[doc(hidden)]
+    pub trait PinnedFieldsOfHelperTrait {
+        type Actual: ?Sized;
+    }
+    #[doc(hidden)]
+    pub struct PinnedFieldsOfHelperStruct<T: ?Sized>(T);
+    impl<T: ?Sized> PinnedFieldsOfHelperTrait for PinnedFieldsOfHelperStruct<T> {
+        type Actual = T;
+    }
+
     // This is an internal helper struct used by `pin-project-internal`.
     //
     // See https://github.com/taiki-e/pin-project/pull/53 for more details.
     #[doc(hidden)]
     pub struct AlwaysUnpin<'a, T>(PhantomData<&'a ()>, PhantomData<T>);
-
     impl<T> Unpin for AlwaysUnpin<'_, T> {}
 
     // This is an internal helper used to ensure a value is dropped.
     #[doc(hidden)]
     pub struct UnsafeDropInPlaceGuard<T: ?Sized>(*mut T);
-
     impl<T: ?Sized> UnsafeDropInPlaceGuard<T> {
         #[doc(hidden)]
         pub unsafe fn new(ptr: *mut T) -> Self {
             Self(ptr)
         }
     }
-
     impl<T: ?Sized> Drop for UnsafeDropInPlaceGuard<T> {
         fn drop(&mut self) {
             // SAFETY: the caller of `UnsafeDropInPlaceGuard::new` must guarantee
@@ -316,14 +329,12 @@ pub mod __private {
         target: *mut T,
         value: ManuallyDrop<T>,
     }
-
     impl<T> UnsafeOverwriteGuard<T> {
         #[doc(hidden)]
         pub unsafe fn new(target: *mut T, value: T) -> Self {
             Self { target, value: ManuallyDrop::new(value) }
         }
     }
-
     impl<T> Drop for UnsafeOverwriteGuard<T> {
         fn drop(&mut self) {
             // SAFETY: the caller of `UnsafeOverwriteGuard::new` must guarantee
diff --git a/tests/expand/default/enum.expanded.rs b/tests/expand/default/enum.expanded.rs
index 7627d2ea..ba6bc6a7 100644
--- a/tests/expand/default/enum.expanded.rs
+++ b/tests/expand/default/enum.expanded.rs
@@ -131,12 +131,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait EnumMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/default/struct.expanded.rs b/tests/expand/default/struct.expanded.rs
index 23338fdf..9cec71e6 100644
--- a/tests/expand/default/struct.expanded.rs
+++ b/tests/expand/default/struct.expanded.rs
@@ -90,12 +90,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait StructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/default/tuple_struct.expanded.rs b/tests/expand/default/tuple_struct.expanded.rs
index 62a75635..8bf51fe7 100644
--- a/tests/expand/default/tuple_struct.expanded.rs
+++ b/tests/expand/default/tuple_struct.expanded.rs
@@ -84,12 +84,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait TupleStructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/multifields/enum.expanded.rs b/tests/expand/multifields/enum.expanded.rs
index 3cf5c1b1..89d0f5f4 100644
--- a/tests/expand/multifields/enum.expanded.rs
+++ b/tests/expand/multifields/enum.expanded.rs
@@ -256,12 +256,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait EnumMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/multifields/struct.expanded.rs b/tests/expand/multifields/struct.expanded.rs
index f1033f99..247e3091 100644
--- a/tests/expand/multifields/struct.expanded.rs
+++ b/tests/expand/multifields/struct.expanded.rs
@@ -143,12 +143,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait StructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/multifields/tuple_struct.expanded.rs b/tests/expand/multifields/tuple_struct.expanded.rs
index 73e571cd..57cb537c 100644
--- a/tests/expand/multifields/tuple_struct.expanded.rs
+++ b/tests/expand/multifields/tuple_struct.expanded.rs
@@ -133,12 +133,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait TupleStructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/naming/enum-all.expanded.rs b/tests/expand/naming/enum-all.expanded.rs
index 65b155f5..a9b30c42 100644
--- a/tests/expand/naming/enum-all.expanded.rs
+++ b/tests/expand/naming/enum-all.expanded.rs
@@ -192,12 +192,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait EnumMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/naming/enum-mut.expanded.rs b/tests/expand/naming/enum-mut.expanded.rs
index 3b9e0200..3996abd9 100644
--- a/tests/expand/naming/enum-mut.expanded.rs
+++ b/tests/expand/naming/enum-mut.expanded.rs
@@ -83,12 +83,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait EnumMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/naming/enum-none.expanded.rs b/tests/expand/naming/enum-none.expanded.rs
index b77a8186..13efed8d 100644
--- a/tests/expand/naming/enum-none.expanded.rs
+++ b/tests/expand/naming/enum-none.expanded.rs
@@ -38,12 +38,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait EnumMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/naming/enum-own.expanded.rs b/tests/expand/naming/enum-own.expanded.rs
index 9ded3d9b..fb37f691 100644
--- a/tests/expand/naming/enum-own.expanded.rs
+++ b/tests/expand/naming/enum-own.expanded.rs
@@ -103,12 +103,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait EnumMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/naming/enum-ref.expanded.rs b/tests/expand/naming/enum-ref.expanded.rs
index df30581b..e02037f6 100644
--- a/tests/expand/naming/enum-ref.expanded.rs
+++ b/tests/expand/naming/enum-ref.expanded.rs
@@ -84,12 +84,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait EnumMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/naming/struct-all.expanded.rs b/tests/expand/naming/struct-all.expanded.rs
index ac664341..ec3fbdc9 100644
--- a/tests/expand/naming/struct-all.expanded.rs
+++ b/tests/expand/naming/struct-all.expanded.rs
@@ -151,12 +151,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait StructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/naming/struct-mut.expanded.rs b/tests/expand/naming/struct-mut.expanded.rs
index 4508f72f..9c93f142 100644
--- a/tests/expand/naming/struct-mut.expanded.rs
+++ b/tests/expand/naming/struct-mut.expanded.rs
@@ -100,12 +100,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait StructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/naming/struct-none.expanded.rs b/tests/expand/naming/struct-none.expanded.rs
index 23338fdf..9cec71e6 100644
--- a/tests/expand/naming/struct-none.expanded.rs
+++ b/tests/expand/naming/struct-none.expanded.rs
@@ -90,12 +90,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait StructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/naming/struct-own.expanded.rs b/tests/expand/naming/struct-own.expanded.rs
index 409f0357..9f623ca6 100644
--- a/tests/expand/naming/struct-own.expanded.rs
+++ b/tests/expand/naming/struct-own.expanded.rs
@@ -131,12 +131,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait StructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/naming/struct-ref.expanded.rs b/tests/expand/naming/struct-ref.expanded.rs
index e4e9445d..6e9d92bc 100644
--- a/tests/expand/naming/struct-ref.expanded.rs
+++ b/tests/expand/naming/struct-ref.expanded.rs
@@ -100,12 +100,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait StructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/naming/tuple_struct-all.expanded.rs b/tests/expand/naming/tuple_struct-all.expanded.rs
index 15ceb4a4..c266d8f2 100644
--- a/tests/expand/naming/tuple_struct-all.expanded.rs
+++ b/tests/expand/naming/tuple_struct-all.expanded.rs
@@ -136,12 +136,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait TupleStructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/naming/tuple_struct-mut.expanded.rs b/tests/expand/naming/tuple_struct-mut.expanded.rs
index b2f847f7..60c99378 100644
--- a/tests/expand/naming/tuple_struct-mut.expanded.rs
+++ b/tests/expand/naming/tuple_struct-mut.expanded.rs
@@ -91,12 +91,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait TupleStructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/naming/tuple_struct-none.expanded.rs b/tests/expand/naming/tuple_struct-none.expanded.rs
index 62a75635..8bf51fe7 100644
--- a/tests/expand/naming/tuple_struct-none.expanded.rs
+++ b/tests/expand/naming/tuple_struct-none.expanded.rs
@@ -84,12 +84,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait TupleStructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/naming/tuple_struct-own.expanded.rs b/tests/expand/naming/tuple_struct-own.expanded.rs
index 2987c4a3..3e4808a6 100644
--- a/tests/expand/naming/tuple_struct-own.expanded.rs
+++ b/tests/expand/naming/tuple_struct-own.expanded.rs
@@ -122,12 +122,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait TupleStructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/naming/tuple_struct-ref.expanded.rs b/tests/expand/naming/tuple_struct-ref.expanded.rs
index ffcd09d8..a5989b76 100644
--- a/tests/expand/naming/tuple_struct-ref.expanded.rs
+++ b/tests/expand/naming/tuple_struct-ref.expanded.rs
@@ -91,12 +91,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait TupleStructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/not_unpin/enum.expanded.rs b/tests/expand/not_unpin/enum.expanded.rs
index ccaaf9be..b1ca08ca 100644
--- a/tests/expand/not_unpin/enum.expanded.rs
+++ b/tests/expand/not_unpin/enum.expanded.rs
@@ -120,17 +120,21 @@ const _: () = {
     #[doc(hidden)]
     impl<'pin, T, U> _pin_project::__private::Unpin for Enum<T, U>
     where
-        _pin_project::__private::Wrapper<
-            'pin,
-            _pin_project::__private::PhantomPinned,
+        ::pin_project::__private::PinnedFieldsOf<
+            _pin_project::__private::Wrapper<
+                'pin,
+                _pin_project::__private::PhantomPinned,
+            >,
         >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Enum<T, U>
     where
-        _pin_project::__private::Wrapper<
-            'pin,
-            _pin_project::__private::PhantomPinned,
+        ::pin_project::__private::PinnedFieldsOf<
+            _pin_project::__private::Wrapper<
+                'pin,
+                _pin_project::__private::PhantomPinned,
+            >,
         >: _pin_project::__private::Unpin,
     {}
     trait EnumMustNotImplDrop {}
diff --git a/tests/expand/not_unpin/struct.expanded.rs b/tests/expand/not_unpin/struct.expanded.rs
index 641508f5..9a9343a8 100644
--- a/tests/expand/not_unpin/struct.expanded.rs
+++ b/tests/expand/not_unpin/struct.expanded.rs
@@ -80,17 +80,21 @@ const _: () = {
     #[doc(hidden)]
     impl<'pin, T, U> _pin_project::__private::Unpin for Struct<T, U>
     where
-        _pin_project::__private::Wrapper<
-            'pin,
-            _pin_project::__private::PhantomPinned,
+        ::pin_project::__private::PinnedFieldsOf<
+            _pin_project::__private::Wrapper<
+                'pin,
+                _pin_project::__private::PhantomPinned,
+            >,
         >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Struct<T, U>
     where
-        _pin_project::__private::Wrapper<
-            'pin,
-            _pin_project::__private::PhantomPinned,
+        ::pin_project::__private::PinnedFieldsOf<
+            _pin_project::__private::Wrapper<
+                'pin,
+                _pin_project::__private::PhantomPinned,
+            >,
         >: _pin_project::__private::Unpin,
     {}
     trait StructMustNotImplDrop {}
diff --git a/tests/expand/not_unpin/tuple_struct.expanded.rs b/tests/expand/not_unpin/tuple_struct.expanded.rs
index b801c081..d63586dc 100644
--- a/tests/expand/not_unpin/tuple_struct.expanded.rs
+++ b/tests/expand/not_unpin/tuple_struct.expanded.rs
@@ -74,17 +74,21 @@ const _: () = {
     #[doc(hidden)]
     impl<'pin, T, U> _pin_project::__private::Unpin for TupleStruct<T, U>
     where
-        _pin_project::__private::Wrapper<
-            'pin,
-            _pin_project::__private::PhantomPinned,
+        ::pin_project::__private::PinnedFieldsOf<
+            _pin_project::__private::Wrapper<
+                'pin,
+                _pin_project::__private::PhantomPinned,
+            >,
         >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for TupleStruct<T, U>
     where
-        _pin_project::__private::Wrapper<
-            'pin,
-            _pin_project::__private::PhantomPinned,
+        ::pin_project::__private::PinnedFieldsOf<
+            _pin_project::__private::Wrapper<
+                'pin,
+                _pin_project::__private::PhantomPinned,
+            >,
         >: _pin_project::__private::Unpin,
     {}
     trait TupleStructMustNotImplDrop {}
diff --git a/tests/expand/pinned_drop/enum.expanded.rs b/tests/expand/pinned_drop/enum.expanded.rs
index c85fffcc..1a260d40 100644
--- a/tests/expand/pinned_drop/enum.expanded.rs
+++ b/tests/expand/pinned_drop/enum.expanded.rs
@@ -132,12 +132,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     impl<T, U> _pin_project::__private::Drop for Enum<T, U> {
         #[allow(clippy::missing_inline_in_public_items)]
diff --git a/tests/expand/pinned_drop/struct.expanded.rs b/tests/expand/pinned_drop/struct.expanded.rs
index 4cdc5fc3..474adfa8 100644
--- a/tests/expand/pinned_drop/struct.expanded.rs
+++ b/tests/expand/pinned_drop/struct.expanded.rs
@@ -91,12 +91,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     impl<T, U> _pin_project::__private::Drop for Struct<T, U> {
         #[allow(clippy::missing_inline_in_public_items)]
diff --git a/tests/expand/pinned_drop/tuple_struct.expanded.rs b/tests/expand/pinned_drop/tuple_struct.expanded.rs
index c1aac0f2..2a25ad72 100644
--- a/tests/expand/pinned_drop/tuple_struct.expanded.rs
+++ b/tests/expand/pinned_drop/tuple_struct.expanded.rs
@@ -85,12 +85,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     impl<T, U> _pin_project::__private::Drop for TupleStruct<T, U> {
         #[allow(clippy::missing_inline_in_public_items)]
diff --git a/tests/expand/project_replace/enum.expanded.rs b/tests/expand/project_replace/enum.expanded.rs
index e3754405..9393123d 100644
--- a/tests/expand/project_replace/enum.expanded.rs
+++ b/tests/expand/project_replace/enum.expanded.rs
@@ -103,12 +103,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait EnumMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/project_replace/struct.expanded.rs b/tests/expand/project_replace/struct.expanded.rs
index 19e74edc..2312bb57 100644
--- a/tests/expand/project_replace/struct.expanded.rs
+++ b/tests/expand/project_replace/struct.expanded.rs
@@ -121,12 +121,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait StructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/project_replace/tuple_struct.expanded.rs b/tests/expand/project_replace/tuple_struct.expanded.rs
index fa7616ea..b367bcf4 100644
--- a/tests/expand/project_replace/tuple_struct.expanded.rs
+++ b/tests/expand/project_replace/tuple_struct.expanded.rs
@@ -115,12 +115,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait TupleStructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/pub/enum.expanded.rs b/tests/expand/pub/enum.expanded.rs
index cebb0c56..aed6ffcb 100644
--- a/tests/expand/pub/enum.expanded.rs
+++ b/tests/expand/pub/enum.expanded.rs
@@ -131,12 +131,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Enum<T, U>
     where
-        __Enum<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Enum<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait EnumMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/pub/struct.expanded.rs b/tests/expand/pub/struct.expanded.rs
index 5281f17b..d84cf00f 100644
--- a/tests/expand/pub/struct.expanded.rs
+++ b/tests/expand/pub/struct.expanded.rs
@@ -90,12 +90,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for Struct<T, U>
     where
-        __Struct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __Struct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait StructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/pub/tuple_struct.expanded.rs b/tests/expand/pub/tuple_struct.expanded.rs
index b48b78fd..4acdf70b 100644
--- a/tests/expand/pub/tuple_struct.expanded.rs
+++ b/tests/expand/pub/tuple_struct.expanded.rs
@@ -84,12 +84,16 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     #[doc(hidden)]
     unsafe impl<'pin, T, U> _pin_project::UnsafeUnpin for TupleStruct<T, U>
     where
-        __TupleStruct<'pin, T, U>: _pin_project::__private::Unpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            __TupleStruct<'pin, T, U>,
+        >: _pin_project::__private::Unpin,
     {}
     trait TupleStructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/unsafe_unpin/enum.expanded.rs b/tests/expand/unsafe_unpin/enum.expanded.rs
index d9445e7e..19f10ade 100644
--- a/tests/expand/unsafe_unpin/enum.expanded.rs
+++ b/tests/expand/unsafe_unpin/enum.expanded.rs
@@ -119,7 +119,9 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Enum<T, U>
     where
-        _pin_project::__private::Wrapper<'pin, Self>: _pin_project::UnsafeUnpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            _pin_project::__private::Wrapper<'pin, Self>,
+        >: _pin_project::UnsafeUnpin,
     {}
     trait EnumMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/unsafe_unpin/struct.expanded.rs b/tests/expand/unsafe_unpin/struct.expanded.rs
index a1cc9cd9..496c2f54 100644
--- a/tests/expand/unsafe_unpin/struct.expanded.rs
+++ b/tests/expand/unsafe_unpin/struct.expanded.rs
@@ -79,7 +79,9 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for Struct<T, U>
     where
-        _pin_project::__private::Wrapper<'pin, Self>: _pin_project::UnsafeUnpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            _pin_project::__private::Wrapper<'pin, Self>,
+        >: _pin_project::UnsafeUnpin,
     {}
     trait StructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/expand/unsafe_unpin/tuple_struct.expanded.rs b/tests/expand/unsafe_unpin/tuple_struct.expanded.rs
index 2ef3ef18..8a2a9111 100644
--- a/tests/expand/unsafe_unpin/tuple_struct.expanded.rs
+++ b/tests/expand/unsafe_unpin/tuple_struct.expanded.rs
@@ -73,7 +73,9 @@ const _: () = {
     }
     impl<'pin, T, U> _pin_project::__private::Unpin for TupleStruct<T, U>
     where
-        _pin_project::__private::Wrapper<'pin, Self>: _pin_project::UnsafeUnpin,
+        ::pin_project::__private::PinnedFieldsOf<
+            _pin_project::__private::Wrapper<'pin, Self>,
+        >: _pin_project::UnsafeUnpin,
     {}
     trait TupleStructMustNotImplDrop {}
     #[allow(clippy::drop_bounds, drop_bounds)]
diff --git a/tests/ui/not_unpin/conflict-unpin.stderr b/tests/ui/not_unpin/conflict-unpin.stderr
index b8a8abc9..dbd785ae 100644
--- a/tests/ui/not_unpin/conflict-unpin.stderr
+++ b/tests/ui/not_unpin/conflict-unpin.stderr
@@ -6,8 +6,6 @@ error[E0119]: conflicting implementations of trait `Unpin` for type `Foo<_, _>`
 ...
 12 | impl<T, U> Unpin for Foo<T, U> where T: Unpin {}
    | --------------------------------------------- first implementation here
-   |
-   = note: upstream crates may add a new impl of trait `std::marker::Unpin` for type `_::_pin_project::__private::Wrapper<'_, std::marker::PhantomPinned>` in future versions
 
 error[E0119]: conflicting implementations of trait `Unpin` for type `Bar<_, _>`
   --> tests/ui/not_unpin/conflict-unpin.rs:14:15
@@ -17,8 +15,6 @@ error[E0119]: conflicting implementations of trait `Unpin` for type `Bar<_, _>`
 ...
 21 | impl<T, U> Unpin for Bar<T, U> {}
    | ------------------------------ first implementation here
-   |
-   = note: upstream crates may add a new impl of trait `std::marker::Unpin` for type `_::_pin_project::__private::Wrapper<'_, std::marker::PhantomPinned>` in future versions
 
 error[E0119]: conflicting implementations of trait `Unpin` for type `Baz<_, _>`
   --> tests/ui/not_unpin/conflict-unpin.rs:23:15
@@ -28,5 +24,3 @@ error[E0119]: conflicting implementations of trait `Unpin` for type `Baz<_, _>`
 ...
 30 | impl<T: Unpin, U: Unpin> Unpin for Baz<T, U> {}
    | -------------------------------------------- first implementation here
-   |
-   = note: upstream crates may add a new impl of trait `std::marker::Unpin` for type `_::_pin_project::__private::Wrapper<'_, std::marker::PhantomPinned>` in future versions
diff --git a/tests/ui/not_unpin/impl-unsafe-unpin.stderr b/tests/ui/not_unpin/impl-unsafe-unpin.stderr
index c889feb2..f00aa5c7 100644
--- a/tests/ui/not_unpin/impl-unsafe-unpin.stderr
+++ b/tests/ui/not_unpin/impl-unsafe-unpin.stderr
@@ -7,7 +7,6 @@ error[E0119]: conflicting implementations of trait `UnsafeUnpin` for type `Foo<_
 12 | unsafe impl<T, U> UnsafeUnpin for Foo<T, U> where T: Unpin {}
    | ---------------------------------------------------------- first implementation here
    |
-   = note: upstream crates may add a new impl of trait `std::marker::Unpin` for type `_::_pin_project::__private::Wrapper<'_, std::marker::PhantomPinned>` in future versions
    = note: this error originates in the derive macro `::pin_project::__private::__PinProjectInternalDerive` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0119]: conflicting implementations of trait `UnsafeUnpin` for type `Bar<_, _>`
@@ -19,7 +18,6 @@ error[E0119]: conflicting implementations of trait `UnsafeUnpin` for type `Bar<_
 21 | unsafe impl<T, U> UnsafeUnpin for Bar<T, U> {}
    | ------------------------------------------- first implementation here
    |
-   = note: upstream crates may add a new impl of trait `std::marker::Unpin` for type `_::_pin_project::__private::Wrapper<'_, std::marker::PhantomPinned>` in future versions
    = note: this error originates in the derive macro `::pin_project::__private::__PinProjectInternalDerive` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0119]: conflicting implementations of trait `UnsafeUnpin` for type `Baz<_, _>`
@@ -31,5 +29,4 @@ error[E0119]: conflicting implementations of trait `UnsafeUnpin` for type `Baz<_
 30 | unsafe impl<T: Unpin, U: Unpin> UnsafeUnpin for Baz<T, U> {}
    | --------------------------------------------------------- first implementation here
    |
-   = note: upstream crates may add a new impl of trait `std::marker::Unpin` for type `_::_pin_project::__private::Wrapper<'_, std::marker::PhantomPinned>` in future versions
    = note: this error originates in the derive macro `::pin_project::__private::__PinProjectInternalDerive` (in Nightly builds, run with -Z macro-backtrace for more info)
diff --git a/tests/ui/pin_project/negative_impls_stable.rs b/tests/ui/pin_project/negative_impls_stable.rs
new file mode 100644
index 00000000..85b81fb6
--- /dev/null
+++ b/tests/ui/pin_project/negative_impls_stable.rs
@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
+// https://github.com/taiki-e/pin-project/issues/340#issuecomment-2428002670
+
+#[pin_project::pin_project]
+struct Foo<Pinned, Unpinned> {
+    #[pin]
+    pinned: Pinned,
+    unpinned: Unpinned,
+}
+
+struct MyPhantomPinned(::core::marker::PhantomPinned);
+impl Unpin for MyPhantomPinned where for<'cursed> str: Sized {}
+impl Unpin for Foo<MyPhantomPinned, ()> {}
+
+fn is_unpin<T: Unpin>() {}
+
+fn main() {
+    is_unpin::<Foo<MyPhantomPinned, ()>>()
+}
diff --git a/tests/ui/pin_project/negative_impls_stable.stderr b/tests/ui/pin_project/negative_impls_stable.stderr
new file mode 100644
index 00000000..5703e376
--- /dev/null
+++ b/tests/ui/pin_project/negative_impls_stable.stderr
@@ -0,0 +1,10 @@
+error[E0119]: conflicting implementations of trait `Unpin` for type `Foo<MyPhantomPinned, ()>`
+  --> tests/ui/pin_project/negative_impls_stable.rs:5:1
+   |
+5  | #[pin_project::pin_project]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `Foo<MyPhantomPinned, ()>`
+...
+14 | impl Unpin for Foo<MyPhantomPinned, ()> {}
+   | --------------------------------------- first implementation here
+   |
+   = note: this error originates in the derive macro `::pin_project::__private::__PinProjectInternalDerive` (in Nightly builds, run with -Z macro-backtrace for more info)
diff --git a/tests/ui/unsafe_unpin/conflict-unpin.stderr b/tests/ui/unsafe_unpin/conflict-unpin.stderr
index b55a5bdc..6838c5d5 100644
--- a/tests/ui/unsafe_unpin/conflict-unpin.stderr
+++ b/tests/ui/unsafe_unpin/conflict-unpin.stderr
@@ -6,8 +6,6 @@ error[E0119]: conflicting implementations of trait `Unpin` for type `Foo<_, _>`
 ...
 12 | impl<T, U> Unpin for Foo<T, U> where T: Unpin {}
    | --------------------------------------------- first implementation here
-   |
-   = note: upstream crates may add a new impl of trait `_::_pin_project::UnsafeUnpin` for type `_::_pin_project::__private::Wrapper<'_, Foo<_, _>>` in future versions
 
 error[E0119]: conflicting implementations of trait `Unpin` for type `Bar<_, _>`
   --> tests/ui/unsafe_unpin/conflict-unpin.rs:14:15
@@ -17,8 +15,6 @@ error[E0119]: conflicting implementations of trait `Unpin` for type `Bar<_, _>`
 ...
 21 | impl<T, U> Unpin for Bar<T, U> {}
    | ------------------------------ first implementation here
-   |
-   = note: upstream crates may add a new impl of trait `_::_pin_project::UnsafeUnpin` for type `_::_pin_project::__private::Wrapper<'_, Bar<_, _>>` in future versions
 
 error[E0119]: conflicting implementations of trait `Unpin` for type `Baz<_, _>`
   --> tests/ui/unsafe_unpin/conflict-unpin.rs:23:15
@@ -28,5 +24,3 @@ error[E0119]: conflicting implementations of trait `Unpin` for type `Baz<_, _>`
 ...
 30 | impl<T: Unpin, U: Unpin> Unpin for Baz<T, U> {}
    | -------------------------------------------- first implementation here
-   |
-   = note: upstream crates may add a new impl of trait `_::_pin_project::UnsafeUnpin` for type `_::_pin_project::__private::Wrapper<'_, Baz<_, _>>` in future versions
diff --git a/tests/run-pass/negative_impls.rs b/tests/ui/unstable-features/negative_impls.rs
similarity index 99%
rename from tests/run-pass/negative_impls.rs
rename to tests/ui/unstable-features/negative_impls.rs
index 007dd720..db29d6c2 100644
--- a/tests/run-pass/negative_impls.rs
+++ b/tests/ui/unstable-features/negative_impls.rs
@@ -9,7 +9,6 @@
 struct Foo<Pinned, Unpinned> {
     #[pin]
     pinned: Pinned,
-
     unpinned: Unpinned,
 }
 
diff --git a/tests/ui/unstable-features/negative_impls.stderr b/tests/ui/unstable-features/negative_impls.stderr
new file mode 100644
index 00000000..57f2d302
--- /dev/null
+++ b/tests/ui/unstable-features/negative_impls.stderr
@@ -0,0 +1,10 @@
+error[E0119]: conflicting implementations of trait `Unpin` for type `Foo<MyPhantomPinned, ()>`
+  --> tests/ui/unstable-features/negative_impls.rs:8:1
+   |
+8  | #[pin_project::pin_project]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `Foo<MyPhantomPinned, ()>`
+...
+17 | impl Unpin for Foo<MyPhantomPinned, ()> {}
+   | --------------------------------------- first implementation here
+   |
+   = note: this error originates in the derive macro `::pin_project::__private::__PinProjectInternalDerive` (in Nightly builds, run with -Z macro-backtrace for more info)