libcxx/include/__chrono/statically_widen.h

   1 // -*- C++ -*-
   2 //===----------------------------------------------------------------------===//
   3 //
   4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   5 // See https://llvm.org/LICENSE.txt for license information.
   6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #ifndef _LIBCPP___CHRONO_STATICALLY_WIDEN_H
  11 #define _LIBCPP___CHRONO_STATICALLY_WIDEN_H
  12
  13 // Implements the STATICALLY-WIDEN exposition-only function. ([time.general]/2)
  14
  15 #include <__concepts/same_as.h>
  16 #include <__config>
  17 #include <__format/concepts.h>
  18
  19 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  20 #  pragma GCC system_header
  21 #endif
  22
  23 _LIBCPP_BEGIN_NAMESPACE_STD
  24
  25 #if _LIBCPP_STD_VER >= 20
  26
  27 #  if _LIBCPP_HAS_WIDE_CHARACTERS
  28 template <__fmt_char_type _CharT>
  29 _LIBCPP_HIDE_FROM_ABI constexpr const _CharT* __statically_widen(const char* __str, const wchar_t* __wstr) {
  30   if constexpr (same_as<_CharT, char>)
  31     return __str;
  32   else
  33     return __wstr;
  34 }
  35 #    define _LIBCPP_STATICALLY_WIDEN(_CharT, __str) ::std::__statically_widen<_CharT>(__str, L##__str)
  36 #  else // _LIBCPP_HAS_WIDE_CHARACTERS
  37
  38 // Without this indirection the unit test test/libcxx/modules_include.sh.cpp
  39 // fails for the CI build "No wide characters". This seems like a bug.
  40 // TODO FMT investigate why this is needed.
  41 template <__fmt_char_type _CharT>
  42 _LIBCPP_HIDE_FROM_ABI constexpr const _CharT* __statically_widen(const char* __str) {
  43   return __str;
  44 }
  45 #    define _LIBCPP_STATICALLY_WIDEN(_CharT, __str) ::std::__statically_widen<_CharT>(__str)
  46 #  endif // _LIBCPP_HAS_WIDE_CHARACTERS
  47
  48 #endif // _LIBCPP_STD_VER >= 20
  49
  50 _LIBCPP_END_NAMESPACE_STD
  51
  52 #endif // _LIBCPP___CHRONO_STATICALLY_WIDEN_H