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/* _mpz_realloc -- make the mpz_t have NEW_ALLOC digits allocated.

Copyright 1991, 1993-1995, 2000, 2001, 2008 Free Software Foundation, Inc.

This file is part of the GNU MP Library.

The GNU MP Library 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 3 of the License, or (at your
option) any later version.

The GNU MP 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 Lesser General Public
License for more details.

You should have received a copy of the GNU Lesser General Public License
along with the GNU MP Library.  If not, see https://www.gnu.org/licenses/.  */

#include <stdlib.h>
#include <stdio.h>
#include "gmp.h"
#include "gmp-impl.h"

void *
_mpz_realloc (mpz_ptr m, mp_size_t new_alloc)
{
  mp_ptr mp;

  /* Never allocate zero space. */
  new_alloc = MAX (new_alloc, 1);

  if (sizeof (mp_size_t) == sizeof (int))
    {
      if (UNLIKELY (new_alloc > ULONG_MAX / GMP_NUMB_BITS))
	{
	  fprintf (stderr, "gmp: overflow in mpz type\n");
	  abort ();
	}
    }
  else
    {
      if (UNLIKELY (new_alloc > INT_MAX))
	{
	  fprintf (stderr, "gmp: overflow in mpz type\n");
	  abort ();
	}
    }

  mp = __GMP_REALLOCATE_FUNC_LIMBS (PTR(m), ALLOC(m), new_alloc);
  PTR(m) = mp;
  ALLOC(m) = new_alloc;

  /* Don't create an invalid number; if the current value doesn't fit after
     reallocation, clear it to 0.  */
  if (ABSIZ(m) > new_alloc)
    SIZ(m) = 0;

  return (void *) mp;
}