[libcxx-commits] [libcxx] [libc++] Add MSVC's implementation of `exception_ptr` for Windows (PR #94977)

[A. Jiang via libcxx-commits]

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@@ -0,0 +1,430 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+// exception standard header
+
+// Copyright (c) Microsoft Corporation.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#ifndef _EXCEPTION_
+#define _EXCEPTION_
+#include <yvals.h>
+#if _STL_COMPILER_PREPROCESSOR
+
+#include <cstdlib>
+#include <type_traits>
+
+#pragma pack(push, _CRT_PACKING)
+#pragma warning(push, _STL_WARNING_LEVEL)
+#pragma warning(disable : _STL_DISABLED_WARNINGS)
+_STL_DISABLE_CLANG_WARNINGS
+#pragma push_macro("new")
+#undef new
+
+_STD_BEGIN
+
+#if _HAS_DEPRECATED_UNCAUGHT_EXCEPTION
+_EXPORT_STD extern "C++" _CXX17_DEPRECATE_UNCAUGHT_EXCEPTION _NODISCARD _CRTIMP2_PURE bool __CLRCALL_PURE_OR_CDECL
+    uncaught_exception() noexcept;
+#endif // _HAS_DEPRECATED_UNCAUGHT_EXCEPTION
+_EXPORT_STD extern "C++" _NODISCARD _CRTIMP2_PURE int __CLRCALL_PURE_OR_CDECL uncaught_exceptions() noexcept;
+
+_STD_END
+
+#if _HAS_EXCEPTIONS
+
+#include <malloc.h> // TRANSITION, VSO-2048380: This is unnecessary, but many projects assume it as of 2024-04-29
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frederick-vs-ja wrote:

Is this also needed for libc++ even though the internal header is newly added?

https://github.com/llvm/llvm-project/pull/94977