--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libcxxabi/src/cxa_guard.cpp	Thu Feb 13 15:10:13 2020 +0900
@@ -0,0 +1,53 @@
+//===---------------------------- cxa_guard.cpp ---------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "__cxxabi_config.h"
+#include "cxxabi.h"
+
+// Tell the implementation that we're building the actual implementation
+// (and not testing it)
+#define BUILDING_CXA_GUARD
+#include "cxa_guard_impl.h"
+
+/*
+    This implementation must be careful to not call code external to this file
+    which will turn around and try to call __cxa_guard_acquire reentrantly.
+    For this reason, the headers of this file are as restricted as possible.
+    Previous implementations of this code for __APPLE__ have used
+    std::__libcpp_mutex_lock and the abort_message utility without problem. This
+    implementation also uses std::__libcpp_condvar_wait which has tested
+    to not be a problem.
+*/
+
+namespace __cxxabiv1 {
+
+#if defined(_LIBCXXABI_GUARD_ABI_ARM)
+using guard_type = uint32_t;
+#else
+using guard_type = uint64_t;
+#endif
+
+extern "C"
+{
+_LIBCXXABI_FUNC_VIS int __cxa_guard_acquire(guard_type* raw_guard_object) {
+  SelectedImplementation imp(raw_guard_object);
+  return static_cast<int>(imp.cxa_guard_acquire());
+}
+
+_LIBCXXABI_FUNC_VIS void __cxa_guard_release(guard_type *raw_guard_object) {
+  SelectedImplementation imp(raw_guard_object);
+  imp.cxa_guard_release();
+}
+
+_LIBCXXABI_FUNC_VIS void __cxa_guard_abort(guard_type *raw_guard_object) {
+  SelectedImplementation imp(raw_guard_object);
+  imp.cxa_guard_abort();
+}
+}  // extern "C"
+
+}  // __cxxabiv1