_M4_LIB_GMP: cover all error cases

Due to bogosity on my part, I managed to get a case not covered by the
macro yet.  The setting of M4_cv_using_lib_gmp=no seems necessary to me
for correct functioning, dunno if you also prefer the warning.

Cheers,
Ralf

2007-01-08  Ralf Wildenhues  <[email protected]>

	* ltdl/m4/gmp.m4 (_M4_LIB_GMP): Cover all error cases.

Index: ltdl/m4/gmp.m4
===================================================================
RCS file: /cvsroot/m4/m4/ltdl/m4/gmp.m4,v
retrieving revision 1.2
diff -u -r1.2 gmp.m4
--- ltdl/m4/gmp.m4	16 Jun 2006 03:51:29 -0000	1.2
+++ ltdl/m4/gmp.m4	8 Jan 2007 19:32:23 -0000
@@ -1,5 +1,5 @@
 # -*- Autoconf -*-
-# Copyright (C) 2000, 2001, 2003, 2006 Free Software Foundation, Inc.
+# Copyright (C) 2000, 2001, 2003, 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
@@ -16,7 +16,7 @@
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 # 02110-1301  USA
 
-# serial 8
+# serial 9
 
 m4_define([_M4_LIB_GMP],
 [AC_ARG_WITH([gmp],
@@ -40,6 +40,10 @@
   no:*)
     M4_cv_using_lib_gmp=no
     ;;
+  *)
+    M4_cv_using_lib_gmp=no
+    AC_MSG_WARN([gmp library not disabled but `gmp.h' missing])
+    ;;
 esac
 ])# _M4_LIB_GMP