diff --git a/library/unwind/src/libunwind.rs b/library/unwind/src/libunwind.rs
index 5e15fe75a24..c8c5528b104 100644
--- a/library/unwind/src/libunwind.rs
+++ b/library/unwind/src/libunwind.rs
@@ -42,6 +42,9 @@ pub enum _Unwind_Reason_Code {
 #[cfg(all(target_arch = "aarch64", target_pointer_width = "32"))]
 pub const unwinder_private_data_size: usize = 5;
 
+#[cfg(target_arch = "m68k")]
+pub const unwinder_private_data_size: usize = 2;
+
 #[cfg(target_arch = "mips")]
 pub const unwinder_private_data_size: usize = 2;