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/* Memory allocation on the stack.

   Copyright (C) 1995, 1999, 2001-2004, 2006-2017 Free Software Foundation,
   Inc.

   This program is free software: you can redistribute it and/or
   modify it under the terms of either:

     * 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.

   or

     * the GNU General Public License as published by the Free
       Software Foundation; either version 2 of the License, or (at your
       option) any later version.

   or both in parallel, as here.
   This program 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.

   You should have received a copy of the GNU General Public
   License along with this program; if not, see
   <https://www.gnu.org/licenses/>.
  */

/* Avoid using the symbol _ALLOCA_H here, as Bison assumes _ALLOCA_H
   means there is a real alloca function.  */
#ifndef _GL_ALLOCA_H
#define _GL_ALLOCA_H

/* alloca (N) returns a pointer to N bytes of memory
   allocated on the stack, which will last until the function returns.
   Use of alloca should be avoided:
     - inside arguments of function calls - undefined behaviour,
     - in inline functions - the allocation may actually last until the
       calling function returns,
     - for huge N (say, N >= 65536) - you never know how large (or small)
       the stack is, and when the stack cannot fulfill the memory allocation
       request, the program just crashes.
 */

#ifndef alloca
# ifdef __GNUC__
#  define alloca __builtin_alloca
# elif defined _AIX
#  define alloca __alloca
# elif defined _MSC_VER
#  include <malloc.h>
#  define alloca _alloca
# elif defined __DECC && defined __VMS
#  define alloca __ALLOCA
# elif defined __TANDEM && defined _TNS_E_TARGET
#  ifdef  __cplusplus
extern "C"
#  endif
void *_alloca (unsigned short);
#  pragma intrinsic (_alloca)
#  define alloca _alloca
# elif defined __MVS__
#  include <stdlib.h>
# else
#  include <stddef.h>
#  ifdef  __cplusplus
extern "C"
#  endif
void *alloca (size_t);
# endif
#endif

#endif /* _GL_ALLOCA_H */