freebsd-dev/contrib/cpio/lib/alloca_.h
2005-10-01 04:37:08 +00:00

55 lines
1.8 KiB
C

/* Memory allocation on the stack.
Copyright (C) 1995, 1999, 2001, 2002, 2003, 2004 Free Software
Foundation, Inc.
This program 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 2, or (at your option)
any later version.
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, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
USA. */
/* When this file is included, it may be preceded only by preprocessor
declarations. Thanks to AIX. Therefore we include it right after
"config.h", not later. */
#ifndef _ALLOCA_H
# define _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.
*/
#ifdef __GNUC__
# define alloca __builtin_alloca
#elif defined _AIX
# define alloca __alloca
#elif defined _MSC_VER
# include <malloc.h>
# define alloca _alloca
#else
# include <stddef.h>
# ifdef __cplusplus
extern "C"
# endif
void *alloca (size_t);
#endif
#endif /* _ALLOCA_H */