diff --git a/source/adios2/engine/hdf5/HDF5ReaderP.cpp b/source/adios2/engine/hdf5/HDF5ReaderP.cpp
index f018718afc..7c81f9f152 100644
--- a/source/adios2/engine/hdf5/HDF5ReaderP.cpp
+++ b/source/adios2/engine/hdf5/HDF5ReaderP.cpp
@@ -146,7 +146,7 @@ size_t HDF5ReaderP::ReadDataset(hid_t dataSetId, hid_t h5Type,
     }
     else
     {
-        hsize_t start[ndims], count[ndims], stride[ndims];
+        std::vector<hsize_t> start(ndims), count(ndims), stride(ndims);
         bool isOrderC = helper::IsRowMajor(m_IO.m_HostLanguage);
 
         for (int i = 0; i < ndims; i++)
@@ -164,12 +164,12 @@ size_t HDF5ReaderP::ReadDataset(hid_t dataSetId, hid_t h5Type,
             slabsize *= count[i];
             stride[i] = 1;
         }
-        hid_t ret = H5Sselect_hyperslab(fileSpace, H5S_SELECT_SET, start,
-                                        stride, count, NULL);
+        hid_t ret = H5Sselect_hyperslab(fileSpace, H5S_SELECT_SET, start.data(),
+                                        stride.data(), count.data(), NULL);
         if (ret < 0)
             return 0;
 
-        hid_t memDataSpace = H5Screate_simple(ndims, count, NULL);
+        hid_t memDataSpace = H5Screate_simple(ndims, count.data(), NULL);
         interop::HDF5TypeGuard g_mds(memDataSpace, interop::E_H5_SPACE);
 
         int elementsRead = 1;
diff --git a/source/adios2/helper/adiosMemory.h b/source/adios2/helper/adiosMemory.h
index 91d5f13534..44a773c1be 100644
--- a/source/adios2/helper/adiosMemory.h
+++ b/source/adios2/helper/adiosMemory.h
@@ -111,14 +111,14 @@ T ReadValue(const std::vector<char> &buffer, size_t &position,
  * @param srcMemCount
  */
 template <class T, class U>
-void CopyMemory(T *dest, const Dims &destStart, const Dims &destCount,
-                const bool destRowMajor, const U *src, const Dims &srcStart,
-                const Dims &srcCount, const bool srcRowMajor,
-                const bool endianReverse = false,
-                const Dims &destMemStart = Dims(),
-                const Dims &destMemCount = Dims(),
-                const Dims &srcMemStart = Dims(),
-                const Dims &srcMemCount = Dims()) noexcept;
+void CopyMemoryBlock(T *dest, const Dims &destStart, const Dims &destCount,
+                     const bool destRowMajor, const U *src,
+                     const Dims &srcStart, const Dims &srcCount,
+                     const bool srcRowMajor, const bool endianReverse = false,
+                     const Dims &destMemStart = Dims(),
+                     const Dims &destMemCount = Dims(),
+                     const Dims &srcMemStart = Dims(),
+                     const Dims &srcMemCount = Dims()) noexcept;
 
 void CopyPayload(char *dest, const Dims &destStart, const Dims &destCount,
                  const bool destRowMajor, const char *src, const Dims &srcStart,
diff --git a/source/adios2/helper/adiosMemory.inl b/source/adios2/helper/adiosMemory.inl
index e130030e92..7ff9d88de6 100644
--- a/source/adios2/helper/adiosMemory.inl
+++ b/source/adios2/helper/adiosMemory.inl
@@ -252,12 +252,12 @@ void ClipVector(std::vector<T> &vec, const size_t start,
 }
 
 template <class T, class U>
-void CopyMemory(T *dest, const Dims &destStart, const Dims &destCount,
-                const bool destRowMajor, const U *src, const Dims &srcStart,
-                const Dims &srcCount, const bool srcRowMajor,
-                const bool endianReverse, const Dims &destMemStart,
-                const Dims &destMemCount, const Dims &srcMemStart,
-                const Dims &srcMemCount) noexcept
+void CopyMemoryBlock(T *dest, const Dims &destStart, const Dims &destCount,
+                     const bool destRowMajor, const U *src,
+                     const Dims &srcStart, const Dims &srcCount,
+                     const bool srcRowMajor, const bool endianReverse,
+                     const Dims &destMemStart, const Dims &destMemCount,
+                     const Dims &srcMemStart, const Dims &srcMemCount) noexcept
 {
     // transform everything to payload dims
     const Dims destStartPayload = PayloadDims<T>(destStart, destRowMajor);
diff --git a/source/adios2/toolkit/format/bp3/BP3Serializer.tcc b/source/adios2/toolkit/format/bp3/BP3Serializer.tcc
index a66b9dc62c..7d54681e6c 100644
--- a/source/adios2/toolkit/format/bp3/BP3Serializer.tcc
+++ b/source/adios2/toolkit/format/bp3/BP3Serializer.tcc
@@ -862,7 +862,7 @@ void BP3Serializer::PutPayloadInBuffer(
     ProfilerStart("memcpy");
     if (!blockInfo.MemoryStart.empty())
     {
-        helper::CopyMemory(
+        helper::CopyMemoryBlock(
             reinterpret_cast<T *>(m_Data.m_Buffer.data() + m_Data.m_Position),
             blockInfo.Start, blockInfo.Count, sourceRowMajor, blockInfo.Data,
             blockInfo.Start, blockInfo.Count, sourceRowMajor, false, Dims(),
diff --git a/source/adios2/toolkit/format/bp4/BP4Serializer.tcc b/source/adios2/toolkit/format/bp4/BP4Serializer.tcc
index 315ae9b46b..fbc62c3573 100644
--- a/source/adios2/toolkit/format/bp4/BP4Serializer.tcc
+++ b/source/adios2/toolkit/format/bp4/BP4Serializer.tcc
@@ -883,7 +883,7 @@ void BP4Serializer::PutPayloadInBuffer(
     if (!blockInfo.MemoryStart.empty())
     {
         // TODO make it a BP4Serializer function
-        helper::CopyMemory(
+        helper::CopyMemoryBlock(
             reinterpret_cast<T *>(m_Data.m_Buffer.data() + m_Data.m_Position),
             blockInfo.Start, blockInfo.Count, sourceRowMajor, blockInfo.Data,
             blockInfo.Start, blockInfo.Count, sourceRowMajor, false, Dims(),
diff --git a/source/adios2/toolkit/interop/hdf5/HDF5Common.cpp b/source/adios2/toolkit/interop/hdf5/HDF5Common.cpp
index 1173e9137f..83bcda2511 100644
--- a/source/adios2/toolkit/interop/hdf5/HDF5Common.cpp
+++ b/source/adios2/toolkit/interop/hdf5/HDF5Common.cpp
@@ -419,8 +419,8 @@ void HDF5Common::AddVar(core::IO &io, std::string const &name, hid_t datasetId,
     {
         hid_t dspace = H5Dget_space(datasetId);
         const int ndims = H5Sget_simple_extent_ndims(dspace);
-        hsize_t dims[ndims];
-        H5Sget_simple_extent_dims(dspace, dims, NULL);
+        std::vector<hsize_t> dims(ndims);
+        H5Sget_simple_extent_dims(dspace, dims.data(), NULL);
         H5Sclose(dspace);
 
         Dims shape;