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/mpq/get_str.c b/third_party/gmp/mpq/get_str.c
new file mode 100644
index 0000000..d0cfb58
--- /dev/null
+++ b/third_party/gmp/mpq/get_str.c
@@ -0,0 +1,80 @@
+/* mpq_get_str -- mpq to string conversion.
+
+Copyright 2001, 2002, 2006, 2011, 2018 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 <stdio.h>
+#include <string.h>
+#include "gmp-impl.h"
+#include "longlong.h"
+
+char *
+mpq_get_str (char *str, int base, mpq_srcptr q)
+{
+  size_t  str_alloc, len;
+
+  if (base > 62 || base < -36)
+    return NULL;
+
+  str_alloc = 0;
+  if (str == NULL)
+    {
+      /* This is an overestimate since we don't bother checking how much of
+	 the high limbs of num and den are used.  +2 for rounding up the
+	 chars per bit of num and den.  +3 for sign, slash and '\0'.  */
+      if (ABS(base) < 2)
+	base = 10;
+      DIGITS_IN_BASE_PER_LIMB (str_alloc, ABSIZ(NUM(q)) + SIZ(DEN(q)), ABS(base));
+      str_alloc += 6;
+
+      str = __GMP_ALLOCATE_FUNC_TYPE (str_alloc, char);
+    }
+
+  mpz_get_str (str, base, mpq_numref(q));
+  len = strlen (str);
+  if (! MPZ_EQUAL_1_P (mpq_denref (q)))
+    {
+      str[len++] = '/';
+      mpz_get_str (str+len, base, mpq_denref(q));
+      len += strlen (str+len);
+    }
+
+  ASSERT (len == strlen(str));
+  ASSERT (str_alloc == 0 || len+1 <= str_alloc);
+  ASSERT (len+1 <= 3 + /* size recommended to applications */
+	  (ABS(base) < 2 ?
+	   mpz_sizeinbase (mpq_numref(q), 10) +
+	   mpz_sizeinbase (mpq_denref(q), 10)
+	   : mpz_sizeinbase (mpq_numref(q), ABS(base)) +
+	   mpz_sizeinbase (mpq_denref(q), ABS(base))));
+
+  if (str_alloc != 0)
+    __GMP_REALLOCATE_FUNC_MAYBE_TYPE (str, str_alloc, len+1, char);
+
+  return str;
+}