1 files changed, 77 insertions, 0 deletions
diff --git a/build-aux/m4/gmp.m4 b/build-aux/m4/gmp.m4
new file mode 100644
index 00000000..36e60516
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+++ b/build-aux/m4/gmp.m4
@@ -0,0 +1,77 @@
+## -*- Autoconf -*-
+## Copyright (C) 2000-2001, 2003, 2006-2008, 2010, 2013 Free Software
+## Foundation, Inc.
+##
+## This file is part of GNU M4.
+##
+## GNU M4 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 of the License, or
+## (at your option) any later version.
+##
+## GNU M4 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, see <http://www.gnu.org/licenses/>.
+
+# serial 10
+
+m4_define([_M4_LIB_GMP],
+[AC_ARG_WITH([gmp],
+  [AS_HELP_STRING([--without-gmp],
+    [don't use GNU multiple precision arithmetic library])],
+[use_gmp=$withval], [use_gmp=yes])
+
+case $use_gmp:$LIBADD_GMP:$ac_cv_header_gmp_h in
+  no:*)
+    M4_cv_using_lib_gmp=no
+    ;;
+  *::yes)
+    AC_MSG_WARN([gmp library not found or does not appear to work
+                 but `gmp.h' is present])
+    M4_cv_using_lib_gmp=no
+    ;;
+  *:-lgmp:no)
+    AC_MSG_WARN([gmp works but `gmp.h' is missing])
+    M4_cv_using_lib_gmp=no
+    ;;
+  yes:*:yes)
+    M4_cv_using_lib_gmp=yes
+    ;;
+  *)
+    M4_cv_using_lib_gmp=no
+    AC_MSG_WARN([could not detect gmp library])
+    ;;
+esac
+])# _M4_LIB_GMP
+
+
+AC_DEFUN([M4_LIB_GMP],
+[AC_PREREQ([2.56])dnl We use the new compiler based header checking in 2.56
+AC_CHECK_HEADERS([gmp.h], [], [], [AC_INCLUDES_DEFAULT])
+m4_pattern_allow([^M4_gmp_save_LIBS$])
+# Some versions of gmp provide mpq_init as a macro, so we need to
+# include the header file, otherwise the detection will fail.
+M4_gmp_save_LIBS="$LIBS"
+LIBS="$LIBS -lgmp"
+AC_LINK_IFELSE([AC_LANG_PROGRAM([[#if HAVE_GMP_H
+#  include <gmp.h>
+#endif]],
+  [[mpq_t n; mpq_init (n);]])],
+  [LIBADD_GMP=-lgmp])
+LIBS=$M4_gmp_save_LIBS
+AC_SUBST([LIBADD_GMP])
+
+_M4_LIB_GMP
+
+# Don't try to link in libgmp if we are not using it after the last call
+if test "$M4_cv_using_lib_gmp" = yes; then
+  AC_DEFINE([USE_GMP], [1],
+    [Define to 1 if using the GNU multiple precision library.])
+fi
+
+AC_SUBST([USE_GMP], [$M4_cv_using_lib_gmp])
+])# M4_LIB_GMP