mirror of
https://github.com/llvm/llvm-project.git
synced 2025-04-27 07:06:06 +00:00
b9a2658a3e
This patch implements the forwarding to frozen C++03 headers as discussed in https://discourse.llvm.org/t/rfc-freezing-c-03-headers-in-libc. In the RFC, we initially proposed selecting the right headers from the Clang driver, however consensus seemed to steer towards handling this in the library itself. This patch implements that direction. At a high level, the changes basically amount to making each public header look like this: ``` // inside <vector> #ifdef _LIBCPP_CXX03_LANG # include <__cxx03/vector> #else // normal <vector> content #endif ``` In most cases, public headers are simple umbrella headers so there isn't much code in the #else branch. In other cases, the #else branch contains the actual implementation of the header.
55 lines
1.3 KiB
C++
55 lines
1.3 KiB
C++
// -*- C++ -*-
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// 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_EXPERIMENTAL_UTILITY
|
|
#define _LIBCPP_EXPERIMENTAL_UTILITY
|
|
|
|
/*
|
|
experimental/utility synopsis
|
|
|
|
// C++1y
|
|
|
|
#include <utility>
|
|
|
|
namespace std {
|
|
namespace experimental {
|
|
inline namespace fundamentals_v1 {
|
|
|
|
3.1.2, erased-type placeholder
|
|
struct erased_type { };
|
|
|
|
} // namespace fundamentals_v1
|
|
} // namespace experimental
|
|
} // namespace std
|
|
|
|
*/
|
|
|
|
#if __cplusplus < 201103L && defined(_LIBCPP_USE_FROZEN_CXX03_HEADERS)
|
|
# include <__cxx03/experimental/utility>
|
|
#else
|
|
# include <__config>
|
|
# include <utility>
|
|
|
|
# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
|
|
# pragma GCC system_header
|
|
# endif
|
|
|
|
_LIBCPP_BEGIN_NAMESPACE_LFTS
|
|
|
|
struct _LIBCPP_TEMPLATE_VIS erased_type {};
|
|
|
|
_LIBCPP_END_NAMESPACE_LFTS
|
|
|
|
# if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
|
|
# include <cstddef>
|
|
# endif
|
|
#endif // __cplusplus < 201103L && defined(_LIBCPP_USE_FROZEN_CXX03_HEADERS)
|
|
|
|
#endif /* _LIBCPP_EXPERIMENTAL_UTILITY */
|