source_location

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// <source_location> -*- C++ -*-
 
// Copyright (C) 2020-2026 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
 
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
 
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
 
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
// <http://www.gnu.org/licenses/>.
 
/** @file include/source_location
 *  This is a Standard C++ Library header.
 */
 
#ifndef _GLIBCXX_SRCLOC
#define _GLIBCXX_SRCLOC 1
 
#define __glibcxx_want_source_location
#include <bits/version.h>
 
#if __cpp_lib_source_location // C++ >= 20 && builtin_source_location
#include <bits/c++config.h>
 
namespace std
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
#ifdef __cpp_lib_contracts
  namespace contracts
  {
    class contract_violation;
  }
#endif // __cpp_lib_contracts
 
  /// A class that describes a location in source code.
  struct source_location
  {
  private:
    using uint_least32_t = __UINT_LEAST32_TYPE__;
    struct __impl
    {
      const char* _M_file_name;
      const char* _M_function_name;
      unsigned _M_line;
      unsigned _M_column;
    };
    using __builtin_ret_type = decltype(__builtin_source_location());
 
  public:
 
    // [support.srcloc.cons], creation
    static consteval source_location
    current(__builtin_ret_type __p = __builtin_source_location()) noexcept
    {
      source_location __ret;
      __ret._M_impl = static_cast <const __impl*>(__p);
      return __ret;
    }
 
    constexpr source_location() noexcept { }
 
    // [support.srcloc.obs], observers
    constexpr uint_least32_t
    line() const noexcept
    { return _M_impl ? _M_impl->_M_line : 0u; }
 
    constexpr uint_least32_t
    column() const noexcept
    { return _M_impl ? _M_impl->_M_column : 0u; }
 
    constexpr const char*
    file_name() const noexcept
    { return _M_impl ? _M_impl->_M_file_name : ""; }
 
    constexpr const char*
    function_name() const noexcept
    { return _M_impl ? _M_impl->_M_function_name : ""; }
 
  private:
    const __impl* _M_impl = nullptr;
 
    constexpr source_location (const void *__t)
      : _M_impl (static_cast <const __impl*>(__t)) {}
 
#ifdef __cpp_lib_contracts
    /* To enable use of the source __impl*.  */
    friend class std::contracts::contract_violation;
#endif // __cpp_lib_contracts
  };
 
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif // __cpp_lib_source_location
#endif // _GLIBCXX_SRCLOC