1 files changed, 1 insertions, 1 deletions

diff --git a/lib/mpi/mpi-cmp.c b/lib/mpi/mpi-cmp.c
index 8ed36b8cbe02..d25e9e96c310 100644
--- a/lib/mpi/mpi-cmp.c
+++ b/lib/mpi/mpi-cmp.c
@@ -57,7 +57,7 @@ int mpi_cmp(MPI u, MPI v)
         if (usize != vsize && !u->sign && !v->sign)
                 return usize - vsize;
         if (usize != vsize && u->sign && v->sign)
-                return vsize + usize;
+                return vsize - usize;
         if (!usize)
                 return 0;
         cmp = mpihelp_cmp(u->d, v->d, usize);