1 files changed, 36 insertions, 0 deletions
diff --git a/m4/gmp.m4 b/m4/gmp.m4
new file mode 100644
index 000000000..3e6033d47
--- /dev/null
+++ b/m4/gmp.m4
@@ -0,0 +1,36 @@
+# Tests for GNU GMP (or any compatible replacement).
+
+dnl Copyright (C) 2008 Free Software Foundation, Inc.
+
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl Written by James Youngman.
+
+dnl Check for libgmp.  We avoid use of AC_CHECK_LIBS because we don't want to
+dnl add this to $LIBS for all targets.
+AC_DEFUN([cu_GMP],
+[
+  LIB_GMP=
+  AC_SUBST([LIB_GMP])
+
+  AC_ARG_WITH([gmp],
+    AS_HELP_STRING([--without-gmp],
+      [do not use the GNU MP library for arbitrary precision
+       calculation (default: use it if available)]),
+    [cu_use_gmp=$withval],
+    [cu_use_gmp=auto])
+
+  if test $cu_use_gmp != no; then
+    cu_saved_libs=$LIBS
+    AC_SEARCH_LIBS([__gmpz_init], [gmp],
+      [test "$ac_cv_search___gmpz_init" = "none required" ||
+       {
+        LIB_GMP=$ac_cv_search___gmpz_init
+        AC_DEFINE([HAVE_GMP], 1,
+          [Define if you have GNU libgmp (or replacement)])
+       }])
+    LIBS=$cu_saved_libs
+  fi
+])