* configure.in (WARNING_CFLAGS): Add -Werror when possible.

(CFLAGS): Do not include the WARNING_CFLAGS here, since GNU
Gettext doesn't compile cleanly, and dies with -Werror.
* src/Makefile.am, lib/Makefile.am, tests/atlocal.in (CFLAGS):
Include WARNING_CFLAGS here.
* lib/xstrdup.c: Include xalloc.h, so that xstrdup be declared
before being defined.

src/Makefile.am

@@ -1,10 +1,29 @@
-## Process this file with automake to produce Makefile.in -*-Makefile-*-
-AUTOMAKE_OPTIONS = 1.4 ../lib/ansi2knr
+## Copyright 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 of the License, 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
+
+AUTOMAKE_OPTIONS = ../lib/ansi2knr
+
 DEFS = @DEFS@ \
   -DBISON_SIMPLE=\"$(pkgdatadir)/bison.simple\" \
   -DBISON_HAIRY=\"$(pkgdatadir)/bison.hairy\" \
   -DLOCALEDIR=\"$(datadir)/locale\"
 
+CFLAGS = @CFLAGS@ $(WARNING_CFLAGS)
+
 # libintl.h in is build/intl, intl/libgettext.h in src/,
 # config.h in build/.
 INCLUDES = -I$(top_builddir)/intl \