69 lines
2.2 KiB
C
69 lines
2.2 KiB
C
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/* Memory allocation on the stack.
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Copyright (C) 1995, 1999, 2001-2003 Free Software Foundation, Inc.
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This program is free software; you can redistribute it and/or modify it
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under the terms of the GNU General Public License as published
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by the Free Software Foundation; either version 2, or (at your option)
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any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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General Public License for more details.
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You should have received a copy of the GNU General Public
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License along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
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USA. */
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/* When this file is included, it may be preceded only by preprocessor
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declarations. Thanks to AIX. Therefore we include it right after
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"config.h", not later. */
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#ifndef _ALLOCA_H
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# define _ALLOCA_H
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/* alloca(N) returns a pointer (void* or char*) to N bytes of memory
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allocated on the stack, and which will last until the function returns.
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Use of alloca should be avoided:
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- inside arguments of function calls - undefined behaviour,
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- in inline functions - the allocation may actually last until the
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calling function returns,
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- for huge N (say, N >= 65536) - you never know how large (or small)
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the stack is, and when the stack cannot fulfill the memory allocation
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request, the program just crashes.
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*/
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# ifdef __GNUC__
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# ifndef alloca
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# define alloca __builtin_alloca
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# endif
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# else
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# ifdef _MSC_VER
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# include <malloc.h>
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# define alloca _alloca
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# else
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# if HAVE_ALLOCA_H
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# include <alloca.h>
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# else
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# ifdef _AIX
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# pragma alloca
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# else
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# ifdef __hpux /* This section must match that of bison generated files. */
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# ifdef __cplusplus
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extern "C" void *alloca (unsigned int);
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# else /* not __cplusplus */
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extern void *alloca ();
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# endif /* not __cplusplus */
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# else /* not __hpux */
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# ifndef alloca
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extern char *alloca ();
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# endif
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# endif /* __hpux */
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# endif
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# endif
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# endif
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# endif
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#endif /* _ALLOCA_H */
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