/* Make free() preserve errno.

   Copyright (C) 2003, 2006, 2009-2023 Free Software Foundation, Inc.

   This file is free software: you can redistribute it and/or modify

   it under the terms of the GNU Lesser General Public License as

   published by the Free Software Foundation; either version 2.1 of the

   License, or (at your option) any later version.

   This file 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 Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public License

   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

/* written by Paul Eggert */

#include <config.h>

/* Specification.  */

#include <stdlib.h>

/* A function definition is only needed if HAVE_FREE_POSIX is not defined.  */

#if !HAVE_FREE_POSIX

# include <errno.h>

void

rpl_free (void *p)

# undef free

{

# if defined __GNUC__ && !defined __clang__

  /* An invalid GCC optimization

     <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98396>

     would optimize away the assignments in the code below, when link-time

     optimization (LTO) is enabled.  Make the code more complicated, so that

     GCC does not grok how to optimize it.  */

  int err[2];

  err[0] = errno;

  err[1] = errno;

  errno = 0;

  free (p);

  errno = err[errno == 0];

# else

  int err = errno;

  free (p);

  errno = err;

# endif

}

#endif