diff --git a/include/atrip/Slice.hpp b/include/atrip/Slice.hpp
index 0990d42..3d12187 100644
--- a/include/atrip/Slice.hpp
+++ b/include/atrip/Slice.hpp
@@ -352,7 +352,7 @@ Info info;
 
 // [[file:~/cuda/atrip/atrip.org::*Attributes][Attributes:2]]
 DataPtr<F> data;
-#if defined(HAVE_CUDA)
+#if defined(HAVE_CUDA && !defined ATRIP_SOURCES_IN_GPU)
     F* mpi_data;
 #endif
 // Attributes:2 ends here
@@ -456,7 +456,7 @@ void unwrapAndMarkReady() {
       if (errorCode != MPI_SUCCESS)
         throw "Atrip: Unexpected error MPI ERROR";
 
-#if defined(HAVE_CUDA)
+#if defined(HAVE_CUDA && !defined ATRIP_SOURCES_IN_GPU)
       // copy the retrieved mpi data to the device
       WITH_CHRONO("cuda:memcpy",
                   _CHECK_CUDA_SUCCESS("copying mpi data to device",
@@ -488,7 +488,7 @@ void unwrapAndMarkReady() {
 Slice(size_t size_)
       : info({})
       , data(DataNullPtr)
-#if defined(HAVE_CUDA)
+#if defined(HAVE_CUDA && !defined ATRIP_SOURCES_IN_GPU)
       , mpi_data(nullptr)
 #endif
       , size(size_)
diff --git a/include/atrip/SliceUnion.hpp b/include/atrip/SliceUnion.hpp
index 0a44fe0..8813c23 100644
--- a/include/atrip/SliceUnion.hpp
+++ b/include/atrip/SliceUnion.hpp
@@ -571,12 +571,11 @@ template <typename F=double>
       if (slice.info.state == Slice<F>::Fetch) { // if-1
         // TODO: do it through the slice class
         slice.info.state = Slice<F>::Dispatched;
-#if defined(HAVE_CUDA)
-#  if !defined(ATRIP_CUDA_AWARE_MPI) && defined(ATRIP_SOURCES_IN_GPU)
+#if defined(HAVE_CUDA && defined ATRIP_SOURCES_IN_GPU)
+#  if !defined(ATRIP_CUDA_AWARE_MPI) 
 #    error "You need CUDA aware MPI to have slices on the GPU"
 #  endif
-        slice.mpi_data = (F*)malloc(sizeof(F) * slice.size);
-        MPI_Irecv(slice.mpi_data,
+        MPI_Irecv((void*)slice.data,
 #else
         MPI_Irecv(slice.data,
 #endif