diff --git a/mpi/mpi-inv.c b/mpi/mpi-inv.c
index 361c57ea4..43e97d897 100644
--- a/mpi/mpi-inv.c
+++ b/mpi/mpi-inv.c
@@ -166,9 +166,9 @@ mpi_invm( MPI x, MPI a, MPI n )
     int odd ;
 
     if (!mpi_cmp_ui (a, 0))
-        return 0; /* Inverse does not exists.  */
+        return; /* Inverse does not exists.  */
     if (!mpi_cmp_ui (n, 1))
-        return 0; /* Inverse does not exists.  */
+        return; /* Inverse does not exists.  */
 
     u = mpi_copy(a);
     v = mpi_copy(n);