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diff --git a/contrib/llvm-project/libcxx/include/__exception/exception.h b/contrib/llvm-project/libcxx/include/__exception/exception.h
new file mode 100644
index 000000000000..3db0126da296
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+++ b/contrib/llvm-project/libcxx/include/__exception/exception.h
@@ -0,0 +1,91 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___EXCEPTION_EXCEPTION_H
+#define _LIBCPP___EXCEPTION_EXCEPTION_H
+
+#include <__config>
+
+// <vcruntime_exception.h> defines its own std::exception and std::bad_exception types,
+// which we use in order to be ABI-compatible with other STLs on Windows.
+#if defined(_LIBCPP_ABI_VCRUNTIME)
+#  include <vcruntime_exception.h>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+namespace std { // purposefully not using versioning namespace
+
+#if defined(_LIBCPP_ABI_VCRUNTIME) && (!defined(_HAS_EXCEPTIONS) || _HAS_EXCEPTIONS != 0)
+// The std::exception class was already included above, but we're explicit about this condition here for clarity.
+
+#elif defined(_LIBCPP_ABI_VCRUNTIME) && _HAS_EXCEPTIONS == 0
+// However, <vcruntime_exception.h> does not define std::exception and std::bad_exception
+// when _HAS_EXCEPTIONS == 0.
+//
+// Since libc++ still wants to provide the std::exception hierarchy even when _HAS_EXCEPTIONS == 0
+// (after all those are simply types like any other), we define an ABI-compatible version
+// of the VCRuntime std::exception and std::bad_exception types in that mode.
+
+struct __std_exception_data {
+  char const* _What;
+  bool _DoFree;
+};
+
+class exception { // base of all library exceptions
+public:
+  exception() _NOEXCEPT : __data_() {}
+
+  explicit exception(char const* __message) _NOEXCEPT : __data_() {
+    __data_._What   = __message;
+    __data_._DoFree = true;
+  }
+
+  exception(exception const&) _NOEXCEPT {}
+
+  exception& operator=(exception const&) _NOEXCEPT { return *this; }
+
+  virtual ~exception() _NOEXCEPT {}
+
+  virtual char const* what() const _NOEXCEPT { return __data_._What ? __data_._What : "Unknown exception"; }
+
+private:
+  __std_exception_data __data_;
+};
+
+class bad_exception : public exception {
+public:
+  bad_exception() _NOEXCEPT : exception("bad exception") {}
+};
+
+#else  // !defined(_LIBCPP_ABI_VCRUNTIME)
+// On all other platforms, we define our own std::exception and std::bad_exception types
+// regardless of whether exceptions are turned on as a language feature.
+
+class _LIBCPP_EXPORTED_FROM_ABI exception {
+public:
+  _LIBCPP_HIDE_FROM_ABI exception() _NOEXCEPT {}
+  _LIBCPP_HIDE_FROM_ABI exception(const exception&) _NOEXCEPT = default;
+
+  virtual ~exception() _NOEXCEPT;
+  virtual const char* what() const _NOEXCEPT;
+};
+
+class _LIBCPP_EXPORTED_FROM_ABI bad_exception : public exception {
+public:
+  _LIBCPP_HIDE_FROM_ABI bad_exception() _NOEXCEPT {}
+  ~bad_exception() _NOEXCEPT override;
+  const char* what() const _NOEXCEPT override;
+};
+#endif // !_LIBCPP_ABI_VCRUNTIME
+
+} // namespace std
+
+#endif // _LIBCPP___EXCEPTION_EXCEPTION_H