Nikolas Klauser b9a2658a3e
[libc++][C++03] Use __cxx03/ headers in C++03 mode (#109002)
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.
2024-12-21 13:01:48 +01:00

61 lines
1.2 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_CLOCALE
#define _LIBCPP_CLOCALE
/*
clocale synopsis
Macros:
LC_ALL
LC_COLLATE
LC_CTYPE
LC_MONETARY
LC_NUMERIC
LC_TIME
NULL
namespace std
{
struct lconv;
char* setlocale(int category, const char* locale);
lconv* localeconv();
} // std
*/
#if __cplusplus < 201103L && defined(_LIBCPP_USE_FROZEN_CXX03_HEADERS)
# include <__cxx03/clocale>
#else
# include <__config>
# if __has_include(<locale.h>)
# include <locale.h>
# endif
# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
# endif
_LIBCPP_BEGIN_NAMESPACE_STD
using ::lconv _LIBCPP_USING_IF_EXISTS;
using ::setlocale _LIBCPP_USING_IF_EXISTS;
using ::localeconv _LIBCPP_USING_IF_EXISTS;
_LIBCPP_END_NAMESPACE_STD
#endif // __cplusplus < 201103L && defined(_LIBCPP_USE_FROZEN_CXX03_HEADERS)
#endif // _LIBCPP_CLOCALE