1 files changed, 18 insertions, 0 deletions
diff --git a/third_party/rust/proc-macro2/src/marker.rs b/third_party/rust/proc-macro2/src/marker.rs
new file mode 100644
index 0000000000..59fd096305
--- /dev/null
+++ b/third_party/rust/proc-macro2/src/marker.rs
@@ -0,0 +1,18 @@
+use core::marker::PhantomData;
+use std::panic::{RefUnwindSafe, UnwindSafe};
+use std::rc::Rc;
+
+// 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(Rc<()>);
+
+impl UnwindSafe for ProcMacroAutoTraits {}
+impl RefUnwindSafe for ProcMacroAutoTraits {}