diff --git a/src/rt/rust_unwind.h b/src/rt/rust_unwind.h
deleted file mode 100644
index 0eb990a9c9b..00000000000
--- a/src/rt/rust_unwind.h
+++ /dev/null
@@ -1,40 +0,0 @@
-// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-// Unwinding stuff missing on some architectures (Mac OS X).
-
-#ifndef RUST_UNWIND_H
-#define RUST_UNWIND_H
-
-#ifdef __APPLE__
-#include <libunwind.h>
-
-typedef void _Unwind_Context;
-typedef int _Unwind_Reason_Code;
-
-#else
-
-#include <unwind.h>
-
-#endif
-
-#if (defined __APPLE__) || (defined __clang__)
-
-#ifndef __FreeBSD__
-
-typedef int _Unwind_Action;
-typedef void _Unwind_Exception;
-
-#endif
-
-#endif
-
-#endif
-
diff --git a/src/rt/rust_upcall.cpp b/src/rt/rust_upcall.cpp
index e524e6de859..59f06feee4b 100644
--- a/src/rt/rust_upcall.cpp
+++ b/src/rt/rust_upcall.cpp
@@ -19,10 +19,16 @@
 #include "rust_globals.h"
 #include "rust_task.h"
 #include "rust_sched_loop.h"
-#include "rust_unwind.h"
 #include "rust_upcall.h"
 #include "rust_util.h"
 
+//Unwinding ABI declarations.
+typedef int _Unwind_Reason_Code;
+typedef int _Unwind_Action;
+
+struct _Unwind_Context;
+struct _Unwind_Exception;
+
 #ifdef __GNUC__
 #define LOG_UPCALL_ENTRY(task)                            \
     LOG(task, upcall,                                     \