cstdlib
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// -*- C++ -*- forwarding header.
// Copyright (C) 1997-2026 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/cstdlib
* This is a Standard C++ Library file. You should @c \#include this file
* in your programs, rather than any of the @a *.h implementation files.
*
* This is the C++ version of the Standard C Library header @c stdlib.h,
* and its contents are (mostly) the same as that header, but are all
* contained in the namespace @c std (except for names which are defined
* as macros in C).
*/
//
// ISO C++ 14882: 20.4.6 C library
//
#ifndef _GLIBCXX_CSTDLIB
#define _GLIBCXX_CSTDLIB 1
#ifdef _GLIBCXX_SYSHDR
#pragma GCC system_header
#endif
#include <bits/c++config.h>
#if !_GLIBCXX_HOSTED
// The C standard does not require a freestanding implementation to
// provide <stdlib.h>. However, the C++ standard does still require
// <cstdlib> -- but only the functionality mentioned in
// [lib.support.start.term].
#define EXIT_SUCCESS 0
#define EXIT_FAILURE 1
#define NULL __null
namespace std
{
extern "C" void abort(void) _GLIBCXX_NOTHROW _GLIBCXX_NORETURN;
extern "C" int atexit(void (*)(void)) _GLIBCXX_NOTHROW;
extern "C" void exit(int) _GLIBCXX_NOTHROW _GLIBCXX_NORETURN;
#if __cplusplus >= 201103L
# ifdef _GLIBCXX_HAVE_AT_QUICK_EXIT
extern "C" int at_quick_exit(void (*)(void)) _GLIBCXX_NOTHROW;
# endif
# ifdef _GLIBCXX_HAVE_QUICK_EXIT
extern "C" void quick_exit(int) _GLIBCXX_NOTHROW _GLIBCXX_NORETURN;
# endif
#if _GLIBCXX_USE_C99_STDLIB
extern "C" void _Exit(int) _GLIBCXX_NOTHROW _GLIBCXX_NORETURN;
#endif
#endif
} // namespace std
#else
// Need to ensure this finds the C library's <stdlib.h> not a libstdc++
// wrapper that might already be installed later in the include search path.
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wpedantic" // include_next
#define _GLIBCXX_INCLUDE_NEXT_C_HEADERS
#include_next <stdlib.h>
#undef _GLIBCXX_INCLUDE_NEXT_C_HEADERS
#pragma GCC diagnostic pop
#include <bits/std_abs.h>
// Get rid of those macros defined in <stdlib.h> in lieu of real functions.
#undef abort
#if __cplusplus >= 201703L && defined(_GLIBCXX_HAVE_ALIGNED_ALLOC)
# undef aligned_alloc
#endif
#undef atexit
#if __cplusplus >= 201103L
# ifdef _GLIBCXX_HAVE_AT_QUICK_EXIT
# undef at_quick_exit
# endif
#endif
#undef atof
#undef atoi
#undef atol
#undef bsearch
#undef calloc
#undef div
#undef exit
#undef free
#undef getenv
#undef labs
#undef ldiv
#undef malloc
#undef mblen
#undef mbstowcs
#undef mbtowc
#undef qsort
#if __cplusplus >= 201103L
# ifdef _GLIBCXX_HAVE_QUICK_EXIT
# undef quick_exit
# endif
#endif
#undef rand
#undef realloc
#undef srand
#undef strtod
#undef strtol
#undef strtoul
#undef system
#undef wcstombs
#undef wctomb
extern "C++"
{
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
using ::div_t;
using ::ldiv_t;
using ::abort;
#if __cplusplus >= 201703L && defined(_GLIBCXX_HAVE_ALIGNED_ALLOC)
using ::aligned_alloc;
#endif
using ::atexit;
#if __cplusplus >= 201103L
# ifdef _GLIBCXX_HAVE_AT_QUICK_EXIT
using ::at_quick_exit;
# endif
#endif
using ::atof;
using ::atoi;
using ::atol;
using ::bsearch;
using ::calloc;
using ::div;
using ::exit;
using ::free;
using ::getenv;
using ::labs;
using ::ldiv;
using ::malloc;
#ifdef _GLIBCXX_HAVE_MBSTATE_T
using ::mblen;
using ::mbstowcs;
using ::mbtowc;
#endif // _GLIBCXX_HAVE_MBSTATE_T
using ::qsort;
#if __cplusplus >= 201103L
# ifdef _GLIBCXX_HAVE_QUICK_EXIT
using ::quick_exit;
# endif
#endif
using ::rand;
using ::realloc;
using ::srand;
using ::strtod;
using ::strtol;
using ::strtoul;
using ::system;
#ifdef _GLIBCXX_USE_WCHAR_T
using ::wcstombs;
using ::wctomb;
#endif // _GLIBCXX_USE_WCHAR_T
#ifndef __CORRECT_ISO_CPP_STDLIB_H_PROTO
inline ldiv_t
div(long __i, long __j) _GLIBCXX_NOTHROW { return ldiv(__i, __j); }
#endif
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
#if _GLIBCXX_USE_C99_STDLIB
#undef _Exit
#undef llabs
#undef lldiv
#undef atoll
#undef strtoll
#undef strtoull
#undef strtof
#undef strtold
namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
#if !_GLIBCXX_USE_C99_LONG_LONG_DYNAMIC
using ::lldiv_t;
#endif
#if _GLIBCXX_USE_C99_CHECK || _GLIBCXX_USE_C99_DYNAMIC
extern "C" void (_Exit)(int) _GLIBCXX_NOTHROW _GLIBCXX_NORETURN;
#endif
#if !_GLIBCXX_USE_C99_DYNAMIC
using ::_Exit;
#endif
#if !_GLIBCXX_USE_C99_LONG_LONG_DYNAMIC
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wlong-long"
using ::llabs;
inline lldiv_t
div(long long __n, long long __d)
{ lldiv_t __q; __q.quot = __n / __d; __q.rem = __n % __d; return __q; }
using ::lldiv;
#pragma GCC diagnostic pop
#endif
#if _GLIBCXX_USE_C99_LONG_LONG_CHECK || _GLIBCXX_USE_C99_LONG_LONG_DYNAMIC
extern "C" long long int (atoll)(const char *) _GLIBCXX_NOTHROW;
extern "C" long long int
(strtoll)(const char * __restrict, char ** __restrict, int) _GLIBCXX_NOTHROW;
extern "C" unsigned long long int
(strtoull)(const char * __restrict, char ** __restrict, int) _GLIBCXX_NOTHROW;
#endif
#if !_GLIBCXX_USE_C99_LONG_LONG_DYNAMIC
using ::atoll;
using ::strtoll;
using ::strtoull;
#endif
using ::strtof;
using ::strtold;
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace __gnu_cxx
namespace std
{
#if !_GLIBCXX_USE_C99_LONG_LONG_DYNAMIC
using ::__gnu_cxx::lldiv_t;
#endif
using ::__gnu_cxx::_Exit;
#if !_GLIBCXX_USE_C99_LONG_LONG_DYNAMIC
using ::__gnu_cxx::llabs;
using ::__gnu_cxx::div;
using ::__gnu_cxx::lldiv;
#endif
using ::__gnu_cxx::atoll;
using ::__gnu_cxx::strtof;
using ::__gnu_cxx::strtoll;
using ::__gnu_cxx::strtoull;
using ::__gnu_cxx::strtold;
} // namespace std
#else // ! _GLIBCXX_USE_C99_STDLIB
// We also check for strtof and strtold separately from _GLIBCXX_USE_C99_STDLIB
#if _GLIBCXX_HAVE_STRTOF
#undef strtof
namespace std { using ::strtof; }
#endif
#if _GLIBCXX_HAVE_STRTOLD
#undef strtold
namespace std { using ::strtold; }
#endif
#endif // _GLIBCXX_USE_C99_STDLIB
} // extern "C++"
#endif // !_GLIBCXX_HOSTED
#endif
std_abs.h
c++config.h
std
ISO C++ entities toplevel namespace is std.
__gnu_cxx
GNU extensions for public use.