Use gnulib's alloca-opt module.

* .bzrignore: Add lib/alloca.h.
* Makefile.in (GNULIB_MODULES): Add alloca-opt.
* configure.in (AC_FUNC_ALLOCA): Remove almost all the alloca stuff,
as gnulib now does that for us.  Put alloca check after gl_INIT.
* lib/gnulib.mk, m4/gl-comp.m4: Regenerate.
* lib/alloca.in.h, m4/alloca.m4: New files, from gnulib.

2 files changed, 80 insertions, 1 deletions

diff --git a/lib/alloca.in.h b/lib/alloca.in.h
new file mode 100644
index 00000000000..5b69c6c81a8
--- /dev/null
+++ b/lib/alloca.in.h
@@ -0,0 +1,56 @@
+/* Memory allocation on the stack.
+
+   Copyright (C) 1995, 1999, 2001-2004, 2006-2011 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 3, 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
+# elif defined __DECC && defined __VMS
+#  define alloca __ALLOCA
+# else
+#  include <stddef.h>
+#  ifdef  __cplusplus
+extern "C"
+#  endif
+void *alloca (size_t);
+# endif
+#endif
+
+#endif /* _GL_ALLOCA_H */
diff --git a/lib/gnulib.mk b/lib/gnulib.mk
index 5987138fafb..0fd7f520acb 100644
--- a/lib/gnulib.mk
+++ b/lib/gnulib.mk
@@ -9,7 +9,7 @@
 # the same distribution terms as the rest of that program.
 #
 # Generated by gnulib-tool.
-# Reproduce by: gnulib-tool --import --dir=. --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=. --makefile-name=gnulib.mk --conditional-dependencies --no-libtool --macro-prefix=gl --no-vc-files careadlinkat crypto/md5 crypto/sha1 crypto/sha256 crypto/sha512 dtoastr filemode getloadavg getopt-gnu ignore-value intprops lstat mktime readlink socklen stdarg stdio strftime strtoumax symlink sys_stat
+# Reproduce by: gnulib-tool --import --dir=. --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=. --makefile-name=gnulib.mk --conditional-dependencies --no-libtool --macro-prefix=gl --no-vc-files alloca-opt careadlinkat crypto/md5 crypto/sha1 crypto/sha256 crypto/sha512 dtoastr filemode getloadavg getopt-gnu ignore-value intprops lstat mktime readlink socklen stdarg stdio strftime strtoumax symlink sys_stat
 
 
 MOSTLYCLEANFILES += core *.stackdump
@@ -21,6 +21,29 @@ libgnu_a_LIBADD = $(gl_LIBOBJS)
 libgnu_a_DEPENDENCIES = $(gl_LIBOBJS)
 EXTRA_libgnu_a_SOURCES =
 
+## begin gnulib module alloca-opt
+
+BUILT_SOURCES += $(ALLOCA_H)
+
+# We need the following in order to create <alloca.h> when the system
+# doesn't have one that works with the given compiler.
+if GL_GENERATE_ALLOCA_H
+alloca.h: alloca.in.h $(top_builddir)/config.status
+        $(AM_V_GEN)rm -f $@-t $@ && \
+        { echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! */'; \
+          cat $(srcdir)/alloca.in.h; \
+        } > $@-t && \
+        mv -f $@-t $@
+else
+alloca.h: $(top_builddir)/config.status
+        rm -f $@
+endif
+MOSTLYCLEANFILES += alloca.h alloca.h-t
+
+EXTRA_DIST += alloca.in.h
+
+## end   gnulib module alloca-opt
+
 ## begin gnulib module allocator
 
 libgnu_a_SOURCES += allocator.c