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+# Check for variable-length arrays.
+
+#serial 1
+
+# From Paul Eggert
+
+# Copyright (C) 2001 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.
+
+AC_DEFUN([AC_C_VARARRAYS],
+[
+  AC_CACHE_CHECK([for variable-length arrays],
+    ac_cv_c_vararrays,
+    [AC_TRY_COMPILE(
+       [],
+       [static int x; char a[++x]; a[sizeof a - 1] = 0; return a[0];],
+       ac_cv_c_vararrays=yes,
+       ac_cv_c_vararrays=no)])
+  if test $ac_cv_c_vararrays = yes; then
+    AC_DEFINE(HAVE_C_VARARRAYS, 1,
+      [Define to 1 if C supports variable-length arrays.])
+  fi
+])