Fix nightly build failure on Gitlab

Found an unused variable warning when building without thread or real
MPI.

Change-Id: I6badc5c32e9eeb07cfafacd3ff9219dd612be847

diff --git a/src/gromacs/taskassignment/taskassignment.cpp b/src/gromacs/taskassignment/taskassignment.cpp
index 03ebb3e50aaacd50972838d17ed41e28168f2980..6df5a4614e651a5e03df7fc159d140446078d222 100644 (file)
--- a/src/gromacs/taskassignment/taskassignment.cpp
+++ b/src/gromacs/taskassignment/taskassignment.cpp
@@ -205,6 +205,8 @@ int countOverAllRanks(MPI_Comm comm, int countOnThisRank)
         MPI_Allreduce(&countOnThisRank, &sum, 1, MPI_INT, MPI_SUM, comm);
     }
     else
+#else
+    GMX_UNUSED_VALUE(comm);
 #endif
     {
         sum = countOnThisRank;