Add -addzero patch to fix bogus results in sympy.

gmpy2-addzero.patch

@@ -0,0 +1,10 @@
+--- src/gmpy2_mpz_inplace.c.orig	2018-04-14 12:27:51.000000000 -0600
++++ src/gmpy2_mpz_inplace.c	2018-06-26 17:33:30.402427832 -0600
+@@ -50,6 +50,7 @@ GMPy_MPZ_IAdd_Slot(PyObject *self, PyObj
+                 mpz_sub_ui(result->z, MPZ(self), ((PyLongObject*)other)->ob_digit[0]);
+                 return (PyObject*)result;
+             case 0:
++                return (PyObject*)result;
+             case 1:
+                 mpz_add_ui(result->z, MPZ(self), ((PyLongObject*)other)->ob_digit[0]);
+                 return (PyObject*)result;

python-gmpy2.spec

@@ -6,7 +6,7 @@
 
 Name:           python-%{srcname}
 Version:        2.1.0
-Release:        0.2.a2%{?dist}
+Release:        0.3.a2%{?dist}
 Summary:        Python interface to GMP, MPFR, and MPC
 
 License:        LGPLv3+
@@ -14,6 +14,8 @@ URL:            https://pypi.python.org/pypi/gmpy2
 Source0:        https://github.com/aleaxit/gmpy/archive/%{srcname}-%{version}a2.tar.gz
 # Fix an import issue; git commit cb0d591
 Patch0:         %{srcname}-import.patch
+# Fix adding by zero in place; https://github.com/aleaxit/gmpy/issues/200
+Patch1:         %{srcname}-addzero.patch
 
 BuildRequires:  gcc
 BuildRequires:  gmp-devel
@@ -70,6 +72,7 @@ Provides:       bundled(jquery)
 mv gmpy-%{srcname}-%{version}a2 python2
 pushd python2
 %patch0
+%patch1
 
 # Fix file encodings.  First the easy one.
 iconv -f ISO8859-1 -t UTF-8 src/gmpy2.c > src/gmpy2.c.utf8
@@ -147,6 +150,9 @@ popd
 %endif
 
 %changelog
+* Tue Jun 26 2018 Jerry James <loganjerry@gmail.com> - 2.1.0-0.3.a2
+- Add -addzero patch to fix bogus results in sympy
+
 * Tue Jun 19 2018 Miro Hrončok <mhroncok@redhat.com> - 2.1.0-0.2.a2
 - Rebuilt for Python 3.7