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diff --git a/third_party/rust/uniffi_bindgen/src/scaffolding/templates/ReexportUniFFIScaffolding.rs b/third_party/rust/uniffi_bindgen/src/scaffolding/templates/ReexportUniFFIScaffolding.rs
new file mode 100644
index 0000000000..0707feef27
--- /dev/null
+++ b/third_party/rust/uniffi_bindgen/src/scaffolding/templates/ReexportUniFFIScaffolding.rs
@@ -0,0 +1,28 @@
+// Code to re-export the UniFFI scaffolding functions.
+//
+// Rust won't always re-export the functions from dependencies
+// ([rust-lang#50007](https://github.com/rust-lang/rust/issues/50007))
+//
+// A workaround for this is to have the dependent crate reference a function from its dependency in
+// an extern "C" function. This is clearly hacky and brittle, but at least we have some unittests
+// that check if this works (fixtures/reexport-scaffolding-macro).
+//
+// The main way we use this macro is for that contain multiple UniFFI components (libxul,
+// megazord).  The combined library has a cargo dependency for each component and calls
+// uniffi_reexport_scaffolding!() for each one.
+
+#[allow(missing_docs)]
+#[doc(hidden)]
+pub const fn uniffi_reexport_hack() {}
+
+#[doc(hidden)]
+#[macro_export]
+macro_rules! uniffi_reexport_scaffolding {
+    () => {
+        #[doc(hidden)]
+        #[no_mangle]
+        pub extern "C" fn {{ ci.namespace() }}_uniffi_reexport_hack() {
+            $crate::uniffi_reexport_hack()
+        }
+    };
+}