Revert "Remove gmp from AOS"

This reverts commit f37c97684f0910a3f241394549392f00145ab0f7.

We need gmp for SymEngine for symbolicmanipultion in C++

Change-Id: Ia13216d1715cf96944f7b4f422b7a799f921d4a4
Signed-off-by: Austin Schuh <austin.linux@gmail.com>
diff --git a/third_party/gmp/cxx/ismpz.cc b/third_party/gmp/cxx/ismpz.cc
new file mode 100644
index 0000000..263ced1
--- /dev/null
+++ b/third_party/gmp/cxx/ismpz.cc
@@ -0,0 +1,62 @@
+/* operator>> -- C++-style input of mpz_t.
+
+Copyright 2001, 2003 Free Software Foundation, Inc.
+
+This file is part of the GNU MP Library.
+
+The GNU MP Library is free software; you can redistribute it and/or modify
+it under the terms of either:
+
+  * the GNU Lesser General Public License as published by the Free
+    Software Foundation; either version 3 of the License, or (at your
+    option) any later version.
+
+or
+
+  * 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.
+
+or both in parallel, as here.
+
+The GNU MP Library 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 copies of the GNU General Public License and the
+GNU Lesser General Public License along with the GNU MP Library.  If not,
+see https://www.gnu.org/licenses/.  */
+
+#include <cctype>
+#include <iostream>
+#include <string>
+#include "gmp-impl.h"
+
+using namespace std;
+
+
+// For g++ libstdc++ parsing see num_get<chartype,initer>::_M_extract_int in
+// include/bits/locale_facets.tcc.
+
+istream &
+operator>> (istream &i, mpz_ptr z)
+{
+  char c = 0;
+  i.get(c); // start reading
+
+  if (i.flags() & ios::skipws) // skip initial whitespace
+    {
+#if HAVE_STD__LOCALE
+      const ctype<char>& ct = use_facet< ctype<char> >(i.getloc());
+#define cxx_isspace(c)  (ct.is(ctype_base::space,(c)))
+#else
+#define cxx_isspace(c)  isspace(c)
+#endif
+
+      while (cxx_isspace(c) && i.get(c))
+        ;
+    }
+
+  return __gmpz_operator_in_nowhite (i, z, c);
+}