zig/lib/libcxx/include/__pstl/handle_exception.h
Alex Rønne Petersen 156ab87500
libcxx: Update to Clang 20.
See:

* https://discourse.llvm.org/t/rfc-freezing-c-03-headers-in-libc/77319
* https://discourse.llvm.org/t/rfc-project-hand-in-hand-llvm-libc-libc-code-sharing/77701

We're dropping support for C++03 for Zig due to the first change; it would be
insane to ship 1018 duplicate header files just for this outdated use case.

As a result of the second change, I had to bring in a subset of the headers from
llvm-libc since libc++ now depends on these. Hopefully we can continue to get
away with not copying the entirety of llvm-libc.
2025-04-04 06:08:09 +02:00

61 lines
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Vendored

//===----------------------------------------------------------------------===//
//
// 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___PSTL_HANDLE_EXCEPTION_H
#define _LIBCPP___PSTL_HANDLE_EXCEPTION_H
#include <__config>
#include <__new/exceptions.h>
#include <__utility/forward.h>
#include <__utility/move.h>
#include <optional>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_PUSH_MACROS
#include <__undef_macros>
#if _LIBCPP_STD_VER >= 17
_LIBCPP_BEGIN_NAMESPACE_STD
namespace __pstl {
template <class _BackendFunction, class... _Args>
_LIBCPP_HIDE_FROM_ABI auto __handle_exception_impl(_Args&&... __args) noexcept {
return _BackendFunction{}(std::forward<_Args>(__args)...);
}
// This function is used to call a backend PSTL algorithm from a frontend algorithm.
//
// All PSTL backend algorithms return an optional denoting whether there was an
// "infrastructure"-level failure (aka failure to allocate). This function takes
// care of unwrapping that and throwing `bad_alloc()` in case there was a problem
// in the underlying implementation.
//
// We must also be careful not to call any user code that could throw an exception
// (such as moving or copying iterators) in here since that should terminate the
// program, which is why we delegate to a noexcept helper below.
template <class _BackendFunction, class... _Args>
_LIBCPP_HIDE_FROM_ABI auto __handle_exception(_Args&&... __args) {
auto __result = __pstl::__handle_exception_impl<_BackendFunction>(std::forward<_Args>(__args)...);
if (__result == nullopt)
std::__throw_bad_alloc();
else
return std::move(*__result);
}
} // namespace __pstl
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP_STD_VER >= 17
_LIBCPP_POP_MACROS
#endif // _LIBCPP___PSTL_HANDLE_EXCEPTION_H