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+/* Memory allocation on the stack.
+
+ Copyright (C) 1995, 1999, 2001-2004, 2006-2007 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+ USA. */
+
+/* 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
+# else
+# include <stddef.h>
+# ifdef __cplusplus
+extern "C"
+# endif
+void *alloca (size_t);
+# endif
+#endif
+
+#endif /* _GL_ALLOCA_H */