diff --git a/src/cpu/VirtualFluidsCore/CoProcessors/MPIIOMigrationBECoProcessor.cpp b/src/cpu/VirtualFluidsCore/CoProcessors/MPIIOMigrationBECoProcessor.cpp
index 0e27f03a9ff1f7e1eb905cdb87e6e5cfcb97454c..d82c594e6b127f2ade7979f8945b057e7ef6db6c 100644
--- a/src/cpu/VirtualFluidsCore/CoProcessors/MPIIOMigrationBECoProcessor.cpp
+++ b/src/cpu/VirtualFluidsCore/CoProcessors/MPIIOMigrationBECoProcessor.cpp
@@ -1054,7 +1054,7 @@ void MPIIOMigrationBECoProcessor::readDataSet(int step)
     rc = MPI_File_open(MPI_COMM_WORLD, filename.c_str(), MPI_MODE_RDONLY, MPI_INFO_NULL, &file_handler);
     if (rc != MPI_SUCCESS)
         throw UbException(UB_EXARGS, "couldn't open file " + filename);
-    int fs = MPI_File_get_size(file_handler, &fsize);
+    MPI_File_get_size(file_handler, &fsize);
     if (fsize > 0)
     {
         multiPhase = true;
diff --git a/src/cpu/VirtualFluidsCore/CoProcessors/MPIIOMigrationCoProcessor.cpp b/src/cpu/VirtualFluidsCore/CoProcessors/MPIIOMigrationCoProcessor.cpp
index d0ce025fda5428a74ec27901202b06acef4781e2..2c5a547c4cca531fe50e7255b0aba6a6a4b5c6e9 100644
--- a/src/cpu/VirtualFluidsCore/CoProcessors/MPIIOMigrationCoProcessor.cpp
+++ b/src/cpu/VirtualFluidsCore/CoProcessors/MPIIOMigrationCoProcessor.cpp
@@ -1707,7 +1707,7 @@ void MPIIOMigrationCoProcessor::readDataSet(int step)
     rc = MPI_File_open(MPI_COMM_WORLD, filename.c_str(), MPI_MODE_RDONLY, MPI_INFO_NULL, &file_handler);
     if (rc != MPI_SUCCESS)
         throw UbException(UB_EXARGS, "couldn't open file " + filename);
-    int fs = MPI_File_get_size(file_handler, &fsize);
+    MPI_File_get_size(file_handler, &fsize);
     if (fsize > 0)
     {
         multiPhase = true;
diff --git a/src/cpu/VirtualFluidsCore/CoProcessors/MPIIORestartCoProcessor.cpp b/src/cpu/VirtualFluidsCore/CoProcessors/MPIIORestartCoProcessor.cpp
index 49277be64ffca7f28a52eb3dfd3a252d1cb4c2fd..036fea0c780bf2a74b22789ee6e0cb605ddbd065 100644
--- a/src/cpu/VirtualFluidsCore/CoProcessors/MPIIORestartCoProcessor.cpp
+++ b/src/cpu/VirtualFluidsCore/CoProcessors/MPIIORestartCoProcessor.cpp
@@ -1715,7 +1715,7 @@ void MPIIORestartCoProcessor::readDataSet(int step)
     rc = MPI_File_open(MPI_COMM_WORLD, filename.c_str(), MPI_MODE_RDONLY, MPI_INFO_NULL, &file_handler);
     if (rc != MPI_SUCCESS)
         throw UbException(UB_EXARGS, "couldn't open file " + filename);
-    int fs = MPI_File_get_size(file_handler, &fsize);
+    MPI_File_get_size(file_handler, &fsize);
     if (fsize > 0)
     {
         multiPhase = true;