1 files changed, 21 insertions, 0 deletions
diff --git a/src/marker.rs b/src/marker.rs
new file mode 100644
index 0000000..e8874bd
--- /dev/null
+++ b/src/marker.rs
@@ -0,0 +1,21 @@
+use alloc::rc::Rc;
+use core::marker::PhantomData;
+use core::panic::{RefUnwindSafe, UnwindSafe};
+
+// Zero sized marker with the correct set of autotrait impls we want all proc
+// macro types to have.
+pub(crate) type Marker = PhantomData<ProcMacroAutoTraits>;
+
+pub(crate) use self::value::*;
+
+mod value {
+    pub(crate) use core::marker::PhantomData as Marker;
+}
+
+pub(crate) struct ProcMacroAutoTraits(
+    #[allow(dead_code)] // https://github.com/rust-lang/rust/issues/119645
+    Rc<()>,
+);
+
+impl UnwindSafe for ProcMacroAutoTraits {}
+impl RefUnwindSafe for ProcMacroAutoTraits {}