From 0a9893e839f3c2a06831162fc9f0ee0793bb296d Mon Sep 17 00:00:00 2001
From: Yixin Lin <1heart@users.noreply.github.com>
Date: Sun, 17 Apr 2022 12:25:17 -0400
Subject: [PATCH] Fix rank>0 thread exiting during SparseGP multiprocessing
 (#731)

If you run mpiexec -n 2 on any code to try to use MPI multiprocessing for SparseGPRegression, it crashes (see #618) because the rank>1 processes do not have ret defined.
---
 GPy/core/sparse_gp_mpi.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/GPy/core/sparse_gp_mpi.py b/GPy/core/sparse_gp_mpi.py
index d9c29a2f..d747ac83 100644
--- a/GPy/core/sparse_gp_mpi.py
+++ b/GPy/core/sparse_gp_mpi.py
@@ -108,6 +108,7 @@ class SparseGP_MPI(SparseGP):
                             raise
                         self._fail_count += 1
                 elif flag==-1:
+                    ret = None
                     break
                 else:
                     self._IN_OPTIMIZATION_ = False