Merge pull request #2300 in HDFFV/hdf5 from ~KMU/hdf5:squashed_cast to develop

* commit 'af5c33afabdae2e39bb45eb1b3e9c8366da01145':
  remove unnecessary stuff
  squash cast warning fix

15 files changed, 365 insertions, 363 deletions

diff --git a/testpar/t_2Gio.c b/testpar/t_2Gio.c
index aebf9cf..e833a0a 100644
--- a/testpar/t_2Gio.c
+++ b/testpar/t_2Gio.c
@@ -285,61 +285,61 @@ slab_set(int mpi_rank, int mpi_size, hsize_t start[], hsize_t count[],
     switch (mode) {
     case BYROW:
         /* Each process takes a slabs of rows. */
-        block[0] = dim0 / mpi_size;
-        block[1] = dim1;
+        block[0] = (hsize_t)dim0 / (hsize_t)mpi_size;
+        block[1] = (hsize_t)dim1;
         stride[0] = block[0];
         stride[1] = block[1];
         count[0] = 1;
         count[1] = 1;
-        start[0] = mpi_rank * block[0];
+        start[0] = (hsize_t)mpi_rank * block[0];
         start[1] = 0;
         if (VERBOSE_MED)
             HDprintf("slab_set BYROW\n");
         break;
     case BYCOL:
         /* Each process takes a block of columns. */
-        block[0] = dim0;
-        block[1] = dim1 / mpi_size;
+        block[0] = (hsize_t)dim0;
+        block[1] = (hsize_t)dim1 / (hsize_t)mpi_size;
         stride[0] = block[0];
         stride[1] = block[1];
         count[0] = 1;
         count[1] = 1;
         start[0] = 0;
-        start[1] = mpi_rank * block[1];
+        start[1] = (hsize_t)mpi_rank * block[1];
         if (VERBOSE_MED)
             HDprintf("slab_set BYCOL\n");
         break;
     case ZROW:
         /* Similar to BYROW except process 0 gets 0 row */
-        block[0] = (mpi_rank ? dim0 / mpi_size : 0);
-        block[1] = dim1;
+        block[0] = (hsize_t)(mpi_rank ? dim0 / mpi_size : 0);
+        block[1] = (hsize_t)dim1;
         stride[0] = (mpi_rank ? block[0] : 1); /* avoid setting stride to 0 */
         stride[1] = block[1];
         count[0] = 1;
         count[1] = 1;
-        start[0] = (mpi_rank ? mpi_rank * block[0] : 0);
+        start[0] = (hsize_t)(mpi_rank ? (hsize_t)mpi_rank * block[0] : 0);
         start[1] = 0;
         if (VERBOSE_MED)
             HDprintf("slab_set ZROW\n");
         break;
     case ZCOL:
         /* Similar to BYCOL except process 0 gets 0 column */
-        block[0] = dim0;
-        block[1] = (mpi_rank ? dim1 / mpi_size : 0);
+        block[0] = (hsize_t)dim0;
+        block[1] = (hsize_t)(mpi_rank ? dim1 / mpi_size : 0);
         stride[0] = block[0];
         stride[1] = (mpi_rank ? block[1] : 1); /* avoid setting stride to 0 */
         count[0] = 1;
         count[1] = 1;
         start[0] = 0;
-        start[1] = (mpi_rank ? mpi_rank * block[1] : 0);
+        start[1] = (hsize_t)(mpi_rank ? (hsize_t)mpi_rank * block[1] : 0);
         if (VERBOSE_MED)
             HDprintf("slab_set ZCOL\n");
         break;
     default:
         /* Unknown mode.  Set it to cover the whole dataset. */
         HDprintf("unknown slab_set mode (%d)\n", mode);
-        block[0] = dim0;
-        block[1] = dim1;
+        block[0] = (hsize_t)dim0;
+        block[1] = (hsize_t)dim1;
         stride[0] = block[0];
         stride[1] = block[1];
         count[0] = 1;
@@ -732,8 +732,8 @@ dataset_writeInd(void)
      * and the slabs local to the MPI process.
      * ------------------------------------------- */
     /* setup dimensionality object */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     sid = H5Screate_simple (MAX_RANK, dims, NULL);
     VRFY((sid >= 0), "H5Screate_simple succeeded");
 
@@ -853,9 +853,9 @@ dataset_readInd(void)
     MPI_Comm_rank(test_comm,&mpi_rank);
 
     /* allocate memory for data buffer */
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 HDmalloc succeeded");
-    data_origin1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_origin1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_origin1 != NULL), "data_origin1 HDmalloc succeeded");
 
     /* setup file access template */
@@ -984,12 +984,12 @@ dataset_writeAll(void)
     MPI_Comm_rank(test_comm,&mpi_rank);
 
     /* set up the coords array selection */
-    num_points = dim1;
-    coords = (hsize_t *)HDmalloc(dim1 * MAX_RANK * sizeof(hsize_t));
+    num_points = (size_t)dim1;
+    coords = (hsize_t *)HDmalloc((size_t)dim1 * (size_t)MAX_RANK * sizeof(hsize_t));
     VRFY((coords != NULL), "coords malloc succeeded");
 
     /* allocate memory for data buffer */
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 HDmalloc succeeded");
 
     /* -------------------
@@ -1013,8 +1013,8 @@ dataset_writeAll(void)
      * and create the dataset
      * ------------------------- */
     /* setup 2-D dimensionality object */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     sid = H5Screate_simple (MAX_RANK, dims, NULL);
     VRFY((sid >= 0), "H5Screate_simple succeeded");
 
@@ -1315,16 +1315,16 @@ dataset_writeAll(void)
 
 
     if(data_array1) free(data_array1);
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 malloc succeeded");
 
     block[0] = 1;
-    block[1] = dim1;
+    block[1] = (hsize_t)dim1;
     stride[0] = 1;
-    stride[1] = dim1;
+    stride[1] = (hsize_t)dim1;
     count[0] = 1;
     count[1] = 1;
-    start[0] = dim0/mpi_size * mpi_rank;
+    start[0] = (hsize_t)dim0/(hsize_t)mpi_size * (hsize_t)mpi_rank;
     start[1] = 0;
 
     dataset_fill(start, block, data_array1);
@@ -1371,7 +1371,7 @@ dataset_writeAll(void)
 
     /* Dataset6: point selection in File - Point selection in Memory*/
     /* create a file dataspace independently */
-    start[0] = dim0/mpi_size * mpi_rank;
+    start[0] = (hsize_t)dim0/(hsize_t)mpi_size * (hsize_t)mpi_rank;
     start[1] = 0;
     point_set (start, count, stride, block, num_points, coords, OUT_OF_ORDER);
     file_dataspace = H5Dget_space (dataset6);
@@ -1409,7 +1409,7 @@ dataset_writeAll(void)
 
     /* Dataset7: point selection in File - All selection in Memory*/
     /* create a file dataspace independently */
-    start[0] = dim0/mpi_size * mpi_rank;
+    start[0] = (hsize_t)dim0/(hsize_t)mpi_size * (hsize_t)mpi_rank;
     start[1] = 0;
     point_set (start, count, stride, block, num_points, coords, IN_ORDER);
     file_dataspace = H5Dget_space (dataset7);
@@ -1515,14 +1515,14 @@ dataset_readAll(void)
     MPI_Comm_rank(test_comm,&mpi_rank);
 
     /* set up the coords array selection */
-    num_points = dim1;
-    coords = (hsize_t *)HDmalloc(dim0 * dim1 * MAX_RANK * sizeof(hsize_t));
+    num_points = (size_t)dim1;
+    coords = (hsize_t *)HDmalloc((size_t)dim0 * (size_t)dim1 * MAX_RANK * sizeof(hsize_t));
     VRFY((coords != NULL), "coords malloc succeeded");
 
     /* allocate memory for data buffer */
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 HDmalloc succeeded");
-    data_origin1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_origin1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_origin1 != NULL), "data_origin1 HDmalloc succeeded");
 
     /* -------------------
@@ -1700,18 +1700,18 @@ dataset_readAll(void)
 
     if(data_array1) free(data_array1);
     if(data_origin1) free(data_origin1);
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 malloc succeeded");
-    data_origin1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_origin1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_origin1 != NULL), "data_origin1 malloc succeeded");
 
     block[0] = 1;
-    block[1] = dim1;
+    block[1] = (hsize_t)dim1;
     stride[0] = 1;
-    stride[1] = dim1;
+    stride[1] = (hsize_t)dim1;
     count[0] = 1;
     count[1] = 1;
-    start[0] = dim0/mpi_size * mpi_rank;
+    start[0] = (hsize_t)dim0/(hsize_t)mpi_size * (hsize_t)mpi_rank;
     start[1] = 0;
 
     dataset_fill(start, block, data_origin1);
@@ -1761,12 +1761,12 @@ dataset_readAll(void)
     H5Pclose(xfer_plist);
 
     if(data_array1) free(data_array1);
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 malloc succeeded");
 
     /* Dataset6: point selection in File - Point selection in Memory*/
     /* create a file dataspace independently */
-    start[0] = dim0/mpi_size * mpi_rank;
+    start[0] = (hsize_t)dim0/(hsize_t)mpi_size * (hsize_t)mpi_rank;
     start[1] = 0;
     point_set (start, count, stride, block, num_points, coords, IN_ORDER);
     file_dataspace = H5Dget_space (dataset6);
@@ -1806,7 +1806,7 @@ dataset_readAll(void)
     H5Pclose(xfer_plist);
 
     if(data_array1) free(data_array1);
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 malloc succeeded");
 
     /* Dataset7: point selection in memory - All selection in file*/
@@ -1816,12 +1816,12 @@ dataset_readAll(void)
     ret = H5Sselect_all(file_dataspace);
     VRFY((ret >= 0), "H5Sselect_all succeeded");
 
-    num_points = dim0 * dim1;
+    num_points = (size_t)dim0 * (size_t)dim1;
     k=0;
     for (i=0 ; i<dim0; i++) {
         for (j=0 ; j<dim1; j++) {
-            coords[k++] = i;
-            coords[k++] = j;
+            coords[k++] = (hsize_t)i;
+            coords[k++] = (hsize_t)j;
         }
     }
     mem_dataspace = H5Dget_space (dataset7);
@@ -1844,7 +1844,7 @@ dataset_readAll(void)
                   xfer_plist, data_array1);
     VRFY((ret >= 0), "H5Dread dataset7 succeeded");
 
-    start[0] = dim0/mpi_size * mpi_rank;
+    start[0] = (hsize_t)dim0/(hsize_t)mpi_size * (hsize_t)mpi_rank;
     start[1] = 0;
     ret = dataset_vrfy(start, count, stride, block, data_array1+(dim0/mpi_size * dim1 * mpi_rank), data_origin1);
     if(ret) nerrors++;
@@ -1927,11 +1927,11 @@ extend_writeInd(void)
     MPI_Comm_rank(test_comm,&mpi_rank);
 
     /* setup chunk-size. Make sure sizes are > 0 */
-    chunk_dims[0] = chunkdim0;
-    chunk_dims[1] = chunkdim1;
+    chunk_dims[0] = (hsize_t)chunkdim0;
+    chunk_dims[1] = (hsize_t)chunkdim1;
 
     /* allocate memory for data buffer */
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 HDmalloc succeeded");
 
     /* -------------------
@@ -2018,8 +2018,8 @@ extend_writeInd(void)
     VRFY((mem_dataspace >= 0), "");
 
     /* Extend its current dim sizes before writing */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     ret = H5Dset_extent(dataset1, dims);
     VRFY((ret >= 0), "H5Dset_extent succeeded");
 
@@ -2078,8 +2078,8 @@ extend_writeInd(void)
     H5Sclose(file_dataspace);
 
     /* Extend dataset2 and try again.  Should succeed. */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     ret = H5Dset_extent(dataset2, dims);
     VRFY((ret >= 0), "H5Dset_extent succeeded");
 
@@ -2240,7 +2240,7 @@ extend_writeInd2(void)
      * Write to the second half of the dataset
      * -------------------------*/
     for (i=0; i<(int)orig_size; i++)
-        written[i] = orig_size + i;
+        H5_CHECKED_ASSIGN(written[i], int, orig_size + (hsize_t)i, hsize_t);
     MESG("data array re-initialized");
     if(VERBOSE_MED) {
     MESG("writing at offset 10: ");
@@ -2315,11 +2315,11 @@ extend_readInd(void)
     MPI_Comm_rank(test_comm,&mpi_rank);
 
     /* allocate memory for data buffer */
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 HDmalloc succeeded");
-    data_array2 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array2 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array2 != NULL), "data_array2 HDmalloc succeeded");
-    data_origin1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_origin1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_origin1 != NULL), "data_origin1 HDmalloc succeeded");
 
     /* -------------------
@@ -2498,11 +2498,11 @@ extend_writeAll(void)
     MPI_Comm_rank(test_comm,&mpi_rank);
 
     /* setup chunk-size. Make sure sizes are > 0 */
-    chunk_dims[0] = chunkdim0;
-    chunk_dims[1] = chunkdim1;
+    chunk_dims[0] = (hsize_t)chunkdim0;
+    chunk_dims[1] = (hsize_t)chunkdim1;
 
     /* allocate memory for data buffer */
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 HDmalloc succeeded");
 
     /* -------------------
@@ -2589,8 +2589,8 @@ extend_writeAll(void)
     VRFY((mem_dataspace >= 0), "");
 
     /* Extend its current dim sizes before writing */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     ret = H5Dset_extent(dataset1, dims);
     VRFY((ret >= 0), "H5Dset_extent succeeded");
 
@@ -2672,8 +2672,8 @@ extend_writeAll(void)
     H5Sclose(file_dataspace);
 
     /* Extend dataset2 and try again.  Should succeed. */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     ret = H5Dset_extent(dataset2, dims);
     VRFY((ret >= 0), "H5Dset_extent succeeded");
 
@@ -2745,11 +2745,11 @@ extend_readAll(void)
     MPI_Comm_rank(test_comm,&mpi_rank);
 
     /* allocate memory for data buffer */
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 HDmalloc succeeded");
-    data_array2 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array2 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array2 != NULL), "data_array2 HDmalloc succeeded");
-    data_origin1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_origin1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_origin1 != NULL), "data_origin1 HDmalloc succeeded");
 
     /* -------------------
@@ -2917,7 +2917,7 @@ compress_readAll(void)
     hid_t dataspace;        /* Dataspace ID */
     hid_t dataset;        /* Dataset ID */
     int rank=1;                 /* Dataspace rank */
-    hsize_t dim=dim0;           /* Dataspace dimensions */
+    hsize_t dim=(hsize_t)dim0;  /* Dataspace dimensions */
     unsigned u;                 /* Local index variable */
     unsigned    chunk_opts;         /* Chunk options */
     unsigned    disable_partial_chunk_filters; /* Whether filters are disabled on partial chunks */
@@ -2945,7 +2945,7 @@ compress_readAll(void)
 
     /* Initialize data buffers */
     for(u=0; u<dim;u++)
-        data_orig[u]=u;
+        data_orig[u]=(DATATYPE)u;
 
     /* Run test both with and without filters disabled on partial chunks */
     for(disable_partial_chunk_filters = 0; disable_partial_chunk_filters <= 1;
@@ -3129,8 +3129,8 @@ none_selection_chunk(void)
     MPI_Comm_rank(test_comm,&mpi_rank);
 
     /* setup chunk-size. Make sure sizes are > 0 */
-    chunk_dims[0] = chunkdim0;
-    chunk_dims[1] = chunkdim1;
+    chunk_dims[0] = (hsize_t)chunkdim0;
+    chunk_dims[1] = (hsize_t)chunkdim1;
 
     /* -------------------
      * START AN HDF5 FILE
@@ -3160,8 +3160,8 @@ none_selection_chunk(void)
     VRFY((ret >= 0), "H5Pset_chunk succeeded");
 
     /* setup dimensionality object */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     sid = H5Screate_simple(MAX_RANK, dims, NULL);
     VRFY((sid >= 0), "H5Screate_simple succeeded");
 
@@ -3438,8 +3438,8 @@ test_actual_io_mode(int selection_mode) {
     VRFY((fid >= 0), "H5Fcreate succeeded");
 
     /* Create the basic Space */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     sid = H5Screate_simple (MAX_RANK, dims, NULL);
     VRFY((sid >= 0), "H5Screate_simple succeeded");
 
@@ -3450,7 +3450,7 @@ test_actual_io_mode(int selection_mode) {
     /* If we are not testing contiguous datasets */
     if(is_chunked) {
         /* Set up chunk information.  */
-        chunk_dims[0] = dims[0]/mpi_size;
+        chunk_dims[0] = dims[0]/(hsize_t)mpi_size;
         chunk_dims[1] = dims[1];
         ret = H5Pset_chunk(dcpl, 2, chunk_dims);
         VRFY((ret >= 0),"chunk creation property list succeeded");
@@ -3516,14 +3516,14 @@ test_actual_io_mode(int selection_mode) {
                  slab_set(mpi_rank, mpi_size, start, count, stride, block, BYCOL);
             } else {
                 /* Select the first and the nth chunk in the nth column */
-                block[0] = dim0 / mpi_size;
-                block[1] = dim1 / mpi_size;
+                block[0] = (hsize_t)(dim0 / mpi_size);
+                block[1] = (hsize_t)(dim1 / mpi_size);
                 count[0] = 2;
                 count[1] = 1;
-                stride[0] = mpi_rank * block[0];
+                stride[0] = (hsize_t)mpi_rank * block[0];
                 stride[1] = 1;
                 start[0] = 0;
-                start[1] = mpi_rank*block[1];
+                start[1] = (hsize_t)mpi_rank*block[1];
             }
 
             test_name = "Multi Chunk - Mixed";
@@ -3554,17 +3554,17 @@ test_actual_io_mode(int selection_mode) {
             if(mpi_rank == 0) {
                  /* Select the first chunk in the first column */
                  slab_set(mpi_rank, mpi_size, start, count, stride, block, BYCOL);
-                 block[0] = block[0] / mpi_size;
+                 block[0] = block[0] / (hsize_t)mpi_size;
             } else {
                 /* Select the first and the nth chunk in the nth column */
-                block[0] = dim0 / mpi_size;
-                block[1] = dim1 / mpi_size;
+                block[0] = (hsize_t)(dim0 / mpi_size);
+                block[1] = (hsize_t)(dim1 / mpi_size);
                 count[0] = 2;
                 count[1] = 1;
-                stride[0] = mpi_rank * block[0];
+                stride[0] = (hsize_t)mpi_rank * block[0];
                 stride[1] = 1;
                 start[0] = 0;
-                start[1] = mpi_rank*block[1];
+                start[1] = (hsize_t)mpi_rank*block[1];
             }
 
             /* If the testname was not already set by the RESET case */
@@ -3637,7 +3637,7 @@ test_actual_io_mode(int selection_mode) {
     length = dim0 * dim1;
 
     /* Allocate and initialize the buffer */
-    buffer = (int *)HDmalloc(sizeof(int) * length);
+    buffer = (int *)HDmalloc(sizeof(int) * (size_t)length);
     VRFY((buffer != NULL), "HDmalloc of buffer succeeded");
     for(i = 0; i < length; i++)
         buffer[i] = i;
@@ -3964,8 +3964,8 @@ test_no_collective_cause_mode(int selection_mode)
             dims[1] = BIG_Y_FACTOR * 6;
         }
         else {
-            dims[0] = dim0;
-            dims[1] = dim1;
+            dims[0] = (hsize_t)dim0;
+            dims[1] = (hsize_t)dim1;
         }
         sid = H5Screate_simple (MAX_RANK, dims, NULL);
         VRFY((sid >= 0), "H5Screate_simple succeeded");
@@ -3987,7 +3987,7 @@ test_no_collective_cause_mode(int selection_mode)
     /* If we are not testing contiguous datasets */
     if(is_chunked) {
         /* Set up chunk information.  */
-        chunk_dims[0] = dims[0]/mpi_size;
+        chunk_dims[0] = dims[0]/(hsize_t)mpi_size;
         chunk_dims[1] = dims[1];
         ret = H5Pset_chunk(dcpl, 2, chunk_dims);
         VRFY((ret >= 0),"chunk creation property list succeeded");
@@ -4068,10 +4068,10 @@ test_no_collective_cause_mode(int selection_mode)
     }
 
     /* Get the number of elements in the selection */
-    length = dims[0] * dims[1];
+    H5_CHECKED_ASSIGN(length, int, dims[0] * dims[1], hsize_t);
 
     /* Allocate and initialize the buffer */
-    buffer = (int *)HDmalloc(sizeof(int) * length);
+    buffer = (int *)HDmalloc(sizeof(int) * (size_t)length);
     VRFY((buffer != NULL), "HDmalloc of buffer succeeded");
     for(i = 0; i < length; i++)
         buffer[i] = i;
@@ -4497,10 +4497,10 @@ dataset_atomicity(void)
 
     buf_size = dim0 * dim1;
     /* allocate memory for data buffer */
-    write_buf = (int *)HDcalloc(buf_size, sizeof(int));
+    write_buf = (int *)HDcalloc((size_t)buf_size, sizeof(int));
     VRFY((write_buf != NULL), "write_buf HDcalloc succeeded");
     /* allocate memory for data buffer */
-    read_buf = (int *)HDcalloc(buf_size, sizeof(int));
+    read_buf = (int *)HDcalloc((size_t)buf_size, sizeof(int));
     VRFY((read_buf != NULL), "read_buf HDcalloc succeeded");
 
     /* setup file access template */
@@ -4516,8 +4516,8 @@ dataset_atomicity(void)
     VRFY((ret >= 0), "H5Pclose succeeded");
 
     /* setup dimensionality object */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     sid = H5Screate_simple (MAX_RANK, dims, NULL);
     VRFY((sid >= 0), "H5Screate_simple succeeded");
 
@@ -4655,10 +4655,10 @@ dataset_atomicity(void)
     VRFY((dataset2 >= 0), "H5Dopen2 succeeded");
 
     /* allocate memory for data buffer */
-    write_buf = (int *)HDcalloc(buf_size, sizeof(int));
+    write_buf = (int *)HDcalloc((size_t)buf_size, sizeof(int));
     VRFY((write_buf != NULL), "write_buf HDcalloc succeeded");
     /* allocate memory for data buffer */
-    read_buf = (int *)HDcalloc(buf_size, sizeof(int));
+    read_buf = (int *)HDcalloc((size_t)buf_size, sizeof(int));
     VRFY((read_buf != NULL), "read_buf HDcalloc succeeded");
 
     for (i=0 ; i<buf_size ; i++) {
@@ -4675,12 +4675,12 @@ dataset_atomicity(void)
     VRFY((atomicity == TRUE), "atomcity set failed");
 
 
-    block[0] = dim0/mpi_size - 1;
-    block[1] = dim1/mpi_size - 1;
+    block[0] = (hsize_t)(dim0/mpi_size) - 1;
+    block[1] = (hsize_t)(dim1/mpi_size) - 1;
     stride[0] = block[0] + 1;
     stride[1] = block[1] + 1;
-    count[0] = mpi_size;
-    count[1] = mpi_size;
+    count[0] = (hsize_t)mpi_size;
+    count[1] = (hsize_t)mpi_size;
     start[0] = 0;
     start[1] = 0;
 
@@ -4736,19 +4736,19 @@ dataset_atomicity(void)
         compare = 5;
 
         for (i=0 ; i<dim0 ; i++) {
-            if ((hsize_t)i >= mpi_rank*(block[0]+1)) {
+            if ((hsize_t)i >= (hsize_t)mpi_rank*(block[0]+1)) {
                 break;
             }
-            if ((i+1)%(block[0]+1)==0) {
+            if (((hsize_t)i+1)%(block[0]+1)==0) {
                 k += dim1;
                 continue;
             }
             for (j=0 ; j<dim1 ; j++) {
-                if ((hsize_t)j >= mpi_rank*(block[1]+1)) {
-                    k += dim1 - mpi_rank*(block[1]+1);
+                if ((hsize_t)j >= (hsize_t)mpi_rank*(block[1]+1)) {
+                    H5_CHECKED_ASSIGN(k, int, (hsize_t)dim1 - (hsize_t)mpi_rank*(block[1]+1) + (hsize_t)k, hsize_t);
                     break;
                 }
-                if ((j+1)%(block[1]+1)==0) {
+                if (((hsize_t)j+1)%(block[1]+1)==0) {
                     k++;
                     continue;
                 }
diff --git a/testpar/t_bigio.c b/testpar/t_bigio.c
index 1bc66b5..45396de 100644
--- a/testpar/t_bigio.c
+++ b/testpar/t_bigio.c
@@ -249,7 +249,7 @@ ccslab_set(int mpi_rank,
     stride[1] =  1;
     count[0]  =  space_dim1;
     count[1]  =  space_dim2;
-    start[0]  =  mpi_rank*count[0];
+    start[0]  =  (hsize_t)mpi_rank*count[0];
     start[1]  =  0;
 
     break;
@@ -258,11 +258,11 @@ ccslab_set(int mpi_rank,
     /* Each process takes several disjoint blocks. */
     block[0]  =  1;
     block[1]  =  1;
-        stride[0] =  3;
-        stride[1] =  3;
-        count[0]  =  space_dim1/(stride[0]*block[0]);
-        count[1]  =  (space_dim2)/(stride[1]*block[1]);
-    start[0]  =  space_dim1*mpi_rank;
+    stride[0] =  3;
+    stride[1] =  3;
+    count[0]  =  space_dim1/(stride[0]*block[0]);
+    count[1]  =  (space_dim2)/(stride[1]*block[1]);
+    start[0]  =  space_dim1*(hsize_t)mpi_rank;
     start[1]  =  0;
 
     break;
@@ -276,7 +276,7 @@ ccslab_set(int mpi_rank,
     stride[1] =  1;
     count[0]  =  ((mpi_rank >= MAX(1,(mpi_size-2)))?0:space_dim1);
     count[1]  =  space_dim2;
-    start[0]  =  mpi_rank*count[0];
+    start[0]  =  (hsize_t)mpi_rank*count[0];
     start[1]  =  0;
 
     break;
@@ -287,14 +287,14 @@ ccslab_set(int mpi_rank,
          half of the domain. */
 
         block[0]  = 1;
-    count[0]  = 2;
-        stride[0] = space_dim1*mpi_size/4+1;
+        count[0]  = 2;
+        stride[0] = (hsize_t)(space_dim1*(hsize_t)mpi_size/4+1);
         block[1]  = space_dim2;
         count[1]  = 1;
         start[1]  = 0;
         stride[1] = 1;
-    if((mpi_rank *3)<(mpi_size*2)) start[0]  = mpi_rank;
-    else start[0] = 1 + space_dim1*mpi_size/2 + (mpi_rank-2*mpi_size/3);
+    if((mpi_rank *3)<(mpi_size*2)) start[0]  = (hsize_t)mpi_rank;
+    else start[0] = 1 + space_dim1*(hsize_t)mpi_size/2 + (hsize_t)(mpi_rank-2*mpi_size/3);
         break;
 
     case BYROW_SELECTINCHUNK:
@@ -302,7 +302,7 @@ ccslab_set(int mpi_rank,
 
         block[0] = 1;
         count[0] = 1;
-    start[0] = mpi_rank*space_dim1;
+    start[0] = (hsize_t)mpi_rank*space_dim1;
         stride[0]= 1;
     block[1] = space_dim2;
     count[1] = 1;
@@ -313,7 +313,7 @@ ccslab_set(int mpi_rank,
 
     default:
     /* Unknown mode.  Set it to cover the whole dataset. */
-    block[0]  = space_dim1*mpi_size;
+    block[0]  = space_dim1*(hsize_t)mpi_size;
     block[1]  = space_dim2;
     stride[0] = block[0];
     stride[1] = block[1];
@@ -521,7 +521,7 @@ dataset_big_write(void)
         HDprintf("\nTesting Dataset1 write by ROW\n");
     /* Create a large dataset */
     dims[0] = bigcount;
-    dims[1] = mpi_size;
+    dims[1] = (hsize_t)mpi_size;
 
     sid = H5Screate_simple (RANK, dims, NULL);
     VRFY((sid >= 0), "H5Screate_simple succeeded");
@@ -529,13 +529,13 @@ dataset_big_write(void)
     VRFY((dataset >= 0), "H5Dcreate2 succeeded");
     H5Sclose(sid);
 
-    block[0] = dims[0]/mpi_size;
+    block[0] = dims[0]/(hsize_t)mpi_size;
     block[1] = dims[1];
     stride[0] = block[0];
     stride[1] = block[1];
     count[0] = 1;
     count[1] = 1;
-    start[0] = mpi_rank*block[0];
+    start[0] = (hsize_t)mpi_rank*block[0];
     start[1] = 0;
 
     /* create a file dataspace independently */
@@ -584,7 +584,7 @@ dataset_big_write(void)
         HDprintf("\nTesting Dataset2 write by COL\n");
     /* Create a large dataset */
     dims[0] = bigcount;
-    dims[1] = mpi_size;
+    dims[1] = (hsize_t)mpi_size;
 
     sid = H5Screate_simple (RANK, dims, NULL);
     VRFY((sid >= 0), "H5Screate_simple succeeded");
@@ -593,13 +593,13 @@ dataset_big_write(void)
     H5Sclose(sid);
 
     block[0] = dims[0];
-    block[1] = dims[1]/mpi_size;
+    block[1] = dims[1]/(hsize_t)mpi_size;
     stride[0] = block[0];
     stride[1] = block[1];
     count[0] = 1;
     count[1] = 1;
     start[0] = 0;
-    start[1] = mpi_rank*block[1];
+    start[1] = (hsize_t)mpi_rank*block[1];
 
     /* create a file dataspace independently */
     file_dataspace = H5Dget_space (dataset);
@@ -710,7 +710,7 @@ dataset_big_write(void)
         HDprintf("\nTesting Dataset4 write point selection\n");
     /* Create a large dataset */
     dims[0] = bigcount;
-    dims[1] = mpi_size * 4;
+    dims[1] = (hsize_t)(mpi_size * 4);
 
     sid = H5Screate_simple (RANK, dims, NULL);
     VRFY((sid >= 0), "H5Screate_simple succeeded");
@@ -725,7 +725,7 @@ dataset_big_write(void)
     count[0] = 1;
     count[1] = 1;
     start[0] = 0;
-    start[1] = dims[1]/mpi_size * mpi_rank;
+    start[1] = dims[1]/(hsize_t)mpi_size * (hsize_t)mpi_rank;
 
     num_points = bigcount;
 
@@ -838,16 +838,16 @@ dataset_big_read(void)
     VRFY((dataset >= 0), "H5Dopen2 succeeded");
 
     dims[0] = bigcount;
-    dims[1] = mpi_size;
+    dims[1] = (hsize_t)mpi_size;
     /* Each process takes a slabs of cols. */
     block[0] = dims[0];
-    block[1] = dims[1]/mpi_size;
+    block[1] = dims[1]/(hsize_t)mpi_size;
     stride[0] = block[0];
     stride[1] = block[1];
     count[0] = 1;
     count[1] = 1;
     start[0] = 0;
-    start[1] = mpi_rank*block[1];
+    start[1] = (hsize_t)mpi_rank*block[1];
 
     /* create a file dataspace independently */
     file_dataspace = H5Dget_space (dataset);
@@ -900,15 +900,15 @@ dataset_big_read(void)
     VRFY((dataset >= 0), "H5Dopen2 succeeded");
 
     dims[0] = bigcount;
-    dims[1] = mpi_size;
+    dims[1] = (hsize_t)mpi_size;
     /* Each process takes a slabs of rows. */
-    block[0] = dims[0]/mpi_size;
+    block[0] = dims[0]/(hsize_t)mpi_size;
     block[1] = dims[1];
     stride[0] = block[0];
     stride[1] = block[1];
     count[0] = 1;
     count[1] = 1;
-    start[0] = mpi_rank*block[0];
+    start[0] = (hsize_t)mpi_rank*block[0];
     start[1] = 0;
 
     /* create a file dataspace independently */
@@ -1024,7 +1024,7 @@ dataset_big_read(void)
     VRFY((dataset >= 0), "H5Dopen2 succeeded");
 
     dims[0] = bigcount;
-    dims[1] = mpi_size * 4;
+    dims[1] = (hsize_t)(mpi_size * 4);
 
     block[0] = dims[0]/2;
     block[1] = 2;
@@ -1033,7 +1033,7 @@ dataset_big_read(void)
     count[0] = 1;
     count[1] = 1;
     start[0] = 0;
-    start[1] = dims[1]/mpi_size * mpi_rank;
+    start[1] = dims[1]/(hsize_t)mpi_size * (hsize_t)mpi_rank;
 
     fill_datasets(start, block, wdata);
     MESG("data_array initialized");
@@ -1463,7 +1463,7 @@ coll_chunktest(const char* filename,
   VRFY((status >= 0),"");
 
   /* setup dimensionality object */
-  dims[0] = space_dim1*mpi_size;
+  dims[0] = space_dim1*(hsize_t)mpi_size;
   dims[1] = space_dim2;
 
   /* allocate memory for data buffer */
@@ -1501,7 +1501,7 @@ coll_chunktest(const char* filename,
   VRFY((crp_plist >= 0),"");
 
   /* Set up chunk information.  */
-  chunk_dims[0] = dims[0]/chunk_factor;
+  chunk_dims[0] = dims[0]/(hsize_t)chunk_factor;
 
   /* to decrease the testing time, maintain bigger chunk size */
   (chunk_factor == 1) ? (chunk_dims[1] = space_dim2) : (chunk_dims[1] = space_dim2/2);
diff --git a/testpar/t_cache.c b/testpar/t_cache.c
index 058cde6..09d2ecc 100644
--- a/testpar/t_cache.c
+++ b/testpar/t_cache.c
@@ -1619,9 +1619,9 @@ serve_read_request(struct mssg_t * mssg_ptr)
             reply.dest      = mssg_ptr->src;
             reply.mssg_num  = -1; /* set by send function */
             reply.base_addr = data[target_index].base_addr;
-            reply.len       = data[target_index].len;
+            H5_CHECKED_ASSIGN(reply.len, unsigned, data[target_index].len, size_t);
             reply.ver       = data[target_index].ver;
-        reply.count     = 0;
+            reply.count     = 0;
             reply.magic     = MSSG_MAGIC;
 
         /* and update the counters */
@@ -1841,7 +1841,7 @@ serve_write_request(struct mssg_t * mssg_ptr)
         reply.dest      = mssg_ptr->src;
         reply.mssg_num  = -1; /* set by send function */
         reply.base_addr = data[target_index].base_addr;
-        reply.len       = data[target_index].len;
+        H5_CHECKED_ASSIGN(reply.len, unsigned, data[target_index].len, size_t);
         reply.ver       = data[target_index].ver;
         reply.count     = 0;
         reply.magic     = MSSG_MAGIC;
@@ -1927,7 +1927,7 @@ serve_total_writes_request(struct mssg_t * mssg_ptr)
         reply.base_addr = 0;
         reply.len       = 0;
         reply.ver       = 0;
-        reply.count     = total_writes;
+        reply.count     = (unsigned)total_writes;
         reply.magic     = MSSG_MAGIC;
     }
 
@@ -2006,7 +2006,7 @@ serve_total_reads_request(struct mssg_t * mssg_ptr)
         reply.base_addr = 0;
         reply.len       = 0;
         reply.ver       = 0;
-        reply.count     = total_reads;
+        reply.count     = (unsigned)total_reads;
         reply.magic     = MSSG_MAGIC;
     }
 
@@ -2100,7 +2100,7 @@ serve_entry_writes_request(struct mssg_t * mssg_ptr)
             reply.base_addr = target_addr;
             reply.len       = 0;
             reply.ver       = 0;
-        reply.count     = data[target_index].writes;
+            reply.count     = (unsigned)data[target_index].writes;
             reply.magic     = MSSG_MAGIC;
         }
     }
@@ -2197,7 +2197,7 @@ serve_entry_reads_request(struct mssg_t * mssg_ptr)
             reply.base_addr = target_addr;
             reply.len       = 0;
             reply.ver       = 0;
-        reply.count     = (long)(data[target_index].reads);
+            reply.count     = (unsigned)(data[target_index].reads);
             reply.magic     = MSSG_MAGIC;
         }
     }
@@ -2633,7 +2633,7 @@ datum_notify(H5C_notify_action_t action, void *thing)
             mssg.dest      = world_server_mpi_rank;
             mssg.mssg_num  = -1; /* set by send function */
             mssg.base_addr = entry_ptr->base_addr;
-            mssg.len       = entry_ptr->len;
+            H5_CHECKED_ASSIGN(mssg.len, unsigned, entry_ptr->len, size_t);
             mssg.ver       = 0; /* bogus -- should be corrected by server */
             mssg.count     = 0; /* not used */
             mssg.magic     = MSSG_MAGIC;
@@ -2789,7 +2789,7 @@ datum_notify(H5C_notify_action_t action, void *thing)
                     mssg.dest      = world_server_mpi_rank;
                     mssg.mssg_num  = -1; /* set by send function */
                     mssg.base_addr = entry_ptr->base_addr;
-                    mssg.len       = entry_ptr->len;
+                    H5_CHECKED_ASSIGN(mssg.len, unsigned, entry_ptr->len, size_t);
                     mssg.ver       = entry_ptr->ver;
                     mssg.count     = 0;
                     mssg.magic     = MSSG_MAGIC;
@@ -4667,7 +4667,7 @@ verify_entry_reads(haddr_t addr,
             }
         } else {
 
-            reported_entry_reads = mssg.count;
+            H5_CHECKED_ASSIGN(reported_entry_reads, int, mssg.count, unsigned);
         }
     }
 
@@ -4774,7 +4774,7 @@ verify_entry_writes(haddr_t addr,
             }
         } else {
 
-            reported_entry_writes = mssg.count;
+            H5_CHECKED_ASSIGN(reported_entry_writes, int, mssg.count, unsigned);
         }
     }
 
@@ -5230,7 +5230,7 @@ server_smoke_check(void)
         mssg.dest      = world_server_mpi_rank;
         mssg.mssg_num  = -1; /* set by send function */
         mssg.base_addr = data[world_mpi_rank].base_addr;
-        mssg.len       = data[world_mpi_rank].len;
+        H5_CHECKED_ASSIGN(mssg.len, unsigned, data[world_mpi_rank].len, size_t);
         mssg.ver       = ++(data[world_mpi_rank].ver);
         mssg.count     = 0;
         mssg.magic     = MSSG_MAGIC;
@@ -5335,7 +5335,7 @@ server_smoke_check(void)
         mssg.dest      = world_server_mpi_rank;
         mssg.mssg_num  = -1; /* set by send function */
         mssg.base_addr = data[world_mpi_rank].base_addr;
-        mssg.len       = data[world_mpi_rank].len;
+        H5_CHECKED_ASSIGN(mssg.len, unsigned, data[world_mpi_rank].len, size_t);
         mssg.ver       = 0; /* bogus -- should be corrected by server */
         mssg.count     = 0;
         mssg.magic     = MSSG_MAGIC;
@@ -7265,7 +7265,8 @@ smoke_check_6(int metadata_write_strategy)
             }
 
             /* Make sure coll entries do not cross the 80% threshold */
-            HDassert(cache_ptr->max_cache_size*0.8 > cache_ptr->coll_list_size);
+            H5_CHECK_OVERFLOW(cache_ptr->max_cache_size, size_t, double);
+            HDassert((double)cache_ptr->max_cache_size*0.8 > cache_ptr->coll_list_size);
         }
 
         /* insert the other half independently */
@@ -7286,7 +7287,7 @@ smoke_check_6(int metadata_write_strategy)
             }
 
             /* Make sure coll entries do not cross the 80% threshold */
-            HDassert(cache_ptr->max_cache_size*0.8 > cache_ptr->coll_list_size);
+            HDassert((double)cache_ptr->max_cache_size*0.8 > cache_ptr->coll_list_size);
         }
 
         /* flush the file */
@@ -7316,7 +7317,7 @@ smoke_check_6(int metadata_write_strategy)
             }
 
             /* Make sure coll entries do not cross the 80% threshold */
-            HDassert(cache_ptr->max_cache_size*0.8 > cache_ptr->coll_list_size);
+            HDassert((double)cache_ptr->max_cache_size*0.8 > cache_ptr->coll_list_size);
         }
 
         /* protect the other half independently */
@@ -7337,7 +7338,7 @@ smoke_check_6(int metadata_write_strategy)
             }
 
             /* Make sure coll entries do not cross the 80% threshold */
-            HDassert(cache_ptr->max_cache_size*0.8 > cache_ptr->coll_list_size);
+            HDassert((double)cache_ptr->max_cache_size*0.8 > cache_ptr->coll_list_size);
         }
 
         for ( i = 0; i < (virt_num_data_entries); i++ )
diff --git a/testpar/t_chunk_alloc.c b/testpar/t_chunk_alloc.c
index bfa0bfe..e6df2d8 100644
--- a/testpar/t_chunk_alloc.c
+++ b/testpar/t_chunk_alloc.c
@@ -95,7 +95,7 @@ create_chunked_dataset(const char *filename, int chunk_factor, write_type write_
     /* Only MAINPROCESS should create the file.  Others just wait. */
     if (MAINPROCESS){
         nchunks=chunk_factor*mpi_size;
-        dims[0]=nchunks*CHUNK_SIZE;
+        dims[0]=(hsize_t)(nchunks*CHUNK_SIZE);
         /* Create the data space with unlimited dimensions. */
         dataspace = H5Screate_simple (1, dims, maxdims);
         VRFY((dataspace >= 0), "");
@@ -127,7 +127,7 @@ create_chunked_dataset(const char *filename, int chunk_factor, write_type write_
             count[0] = 1;
             stride[0] = 1;
             block[0] = chunk_dims[0];
-            offset[0] = (nchunks-2)*chunk_dims[0];
+            offset[0] = (hsize_t)(nchunks-2)*chunk_dims[0];
 
             hrc = H5Sselect_hyperslab(dataspace, H5S_SELECT_SET, offset, stride, count, block);
                 VRFY((hrc >= 0), "");
@@ -157,7 +157,7 @@ create_chunked_dataset(const char *filename, int chunk_factor, write_type write_
 
         /* verify file size */
         filesize = get_filesize(filename);
-        est_filesize = nchunks * CHUNK_SIZE * sizeof(unsigned char);
+        est_filesize = (MPI_Offset)nchunks * (MPI_Offset)CHUNK_SIZE * (MPI_Offset)sizeof(unsigned char);
         VRFY((filesize >= est_filesize), "file size check");
 
     }
@@ -233,7 +233,7 @@ parallel_access_dataset(const char *filename, int chunk_factor, access_type acti
     dataspace = H5Dget_space(*dataset);
     VRFY((dataspace >= 0), "");
 
-    size[0] = nchunks*CHUNK_SIZE;
+    size[0] = (hsize_t)nchunks*CHUNK_SIZE;
 
     switch (action) {
 
@@ -245,7 +245,7 @@ parallel_access_dataset(const char *filename, int chunk_factor, access_type acti
             stride[0] = 1;
             block[0] = chunk_dims[0];
             for (i=0; i<nchunks/mpi_size; i++) {
-                offset[0] = (i*mpi_size+mpi_rank)*chunk_dims[0];
+                offset[0] = (hsize_t)(i*mpi_size+mpi_rank)*chunk_dims[0];
 
                 hrc = H5Sselect_hyperslab(dataspace, H5S_SELECT_SET, offset, stride, count, block);
                 VRFY((hrc >= 0), "");
@@ -294,7 +294,7 @@ parallel_access_dataset(const char *filename, int chunk_factor, access_type acti
 
     /* verify file size */
     filesize = get_filesize(filename);
-    est_filesize = nchunks*CHUNK_SIZE*sizeof(unsigned char);
+    est_filesize = (MPI_Offset)nchunks*(MPI_Offset)CHUNK_SIZE*(MPI_Offset)sizeof(unsigned char);
     VRFY((filesize >= est_filesize), "file size check");
 
     /* Can close some plists */
@@ -374,7 +374,7 @@ verify_data(const char *filename, int chunk_factor, write_type write_pattern, in
         /* reset buffer values */
         HDmemset(buffer, -1, CHUNK_SIZE);
 
-        offset[0] = i*chunk_dims[0];
+        offset[0] = (hsize_t)i*chunk_dims[0];
 
         hrc = H5Sselect_hyperslab(dataspace, H5S_SELECT_SET, offset, stride, count, block);
         VRFY((hrc >= 0), "");
diff --git a/testpar/t_coll_chunk.c b/testpar/t_coll_chunk.c
index 2d758ba..e950015 100644
--- a/testpar/t_coll_chunk.c
+++ b/testpar/t_coll_chunk.c
@@ -637,7 +637,7 @@ coll_chunktest(const char* filename,
   VRFY((status >= 0),"");
 
   /* setup dimensionality object */
-  dims[0] = SPACE_DIM1*mpi_size;
+  dims[0] = (hsize_t)(SPACE_DIM1*mpi_size);
   dims[1] = SPACE_DIM2;
 
   /* allocate memory for data buffer */
@@ -670,7 +670,7 @@ coll_chunktest(const char* filename,
   VRFY((crp_plist >= 0),"");
 
   /* Set up chunk information.  */
-  chunk_dims[0] = dims[0]/chunk_factor;
+  chunk_dims[0] = dims[0]/(hsize_t)chunk_factor;
 
   /* to decrease the testing time, maintain bigger chunk size */
   (chunk_factor == 1) ? (chunk_dims[1] = SPACE_DIM2) : (chunk_dims[1] = SPACE_DIM2/2);
@@ -1057,7 +1057,7 @@ ccslab_set(int mpi_rank,
 	stride[1] =  1;
 	count[0]  =  SPACE_DIM1;
 	count[1]  =  SPACE_DIM2;
-	start[0]  =  mpi_rank*count[0];
+	start[0]  =  (hsize_t)mpi_rank*count[0];
 	start[1]  =  0;
 
 	break;
@@ -1066,11 +1066,11 @@ ccslab_set(int mpi_rank,
 	/* Each process takes several disjoint blocks. */
 	block[0]  =  1;
 	block[1]  =  1;
-        stride[0] =  3;
-        stride[1] =  3;
-        count[0]  =  SPACE_DIM1/(stride[0]*block[0]);
-        count[1]  =  (SPACE_DIM2)/(stride[1]*block[1]);
-	start[0]  =  SPACE_DIM1*mpi_rank;
+    stride[0] =  3;
+    stride[1] =  3;
+    count[0]  =  SPACE_DIM1/(stride[0]*block[0]);
+    count[1]  =  (SPACE_DIM2)/(stride[1]*block[1]);
+	start[0]  =  (hsize_t)SPACE_DIM1*(hsize_t)mpi_rank;
 	start[1]  =  0;
 
 	break;
@@ -1084,7 +1084,7 @@ ccslab_set(int mpi_rank,
 	stride[1] =  1;
 	count[0]  =  ((mpi_rank >= MAX(1,(mpi_size-2)))?0:SPACE_DIM1);
 	count[1]  =  SPACE_DIM2;
-	start[0]  =  mpi_rank*count[0];
+	start[0]  =  (hsize_t)mpi_rank*count[0];
 	start[1]  =  0;
 
 	break;
@@ -1095,14 +1095,14 @@ ccslab_set(int mpi_rank,
          half of the domain. */
 
         block[0]  = 1;
-	count[0]  = 2;
-        stride[0] = SPACE_DIM1*mpi_size/4+1;
+	    count[0]  = 2;
+        stride[0] = (hsize_t)SPACE_DIM1*(hsize_t)mpi_size/4+1;
         block[1]  = SPACE_DIM2;
         count[1]  = 1;
         start[1]  = 0;
         stride[1] = 1;
-	if((mpi_rank *3)<(mpi_size*2)) start[0]  = mpi_rank;
-	else start[0] = 1 + SPACE_DIM1*mpi_size/2 + (mpi_rank-2*mpi_size/3);
+	if((mpi_rank *3)<(mpi_size*2)) start[0]  = (hsize_t)mpi_rank;
+	else start[0] = (hsize_t)(1 + SPACE_DIM1*mpi_size/2 + (mpi_rank-2*mpi_size/3));
         break;
 
     case BYROW_SELECTINCHUNK:
@@ -1110,7 +1110,7 @@ ccslab_set(int mpi_rank,
 
         block[0] = 1;
         count[0] = 1;
-	start[0] = mpi_rank*SPACE_DIM1;
+	start[0] = (hsize_t)(mpi_rank*SPACE_DIM1);
         stride[0]= 1;
 	block[1] = SPACE_DIM2;
 	count[1] = 1;
@@ -1121,7 +1121,7 @@ ccslab_set(int mpi_rank,
 
     default:
 	/* Unknown mode.  Set it to cover the whole dataset. */
-	block[0]  = SPACE_DIM1*mpi_size;
+	block[0]  = (hsize_t)SPACE_DIM1*(hsize_t)mpi_size;
 	block[1]  = SPACE_DIM2;
 	stride[0] = block[0];
 	stride[1] = block[1];
diff --git a/testpar/t_coll_md_read.c b/testpar/t_coll_md_read.c
index c0fe04b..d4b2106 100644
--- a/testpar/t_coll_md_read.c
+++ b/testpar/t_coll_md_read.c
@@ -96,8 +96,8 @@ void test_partial_no_selection_coll_md_read(void)
     dataset_dims = HDmalloc(PARTIAL_NO_SELECTION_DATASET_NDIMS * sizeof(*dataset_dims));
     VRFY((dataset_dims != NULL), "malloc succeeded");
 
-    dataset_dims[0] = PARTIAL_NO_SELECTION_Y_DIM_SCALE * mpi_size;
-    dataset_dims[1] = PARTIAL_NO_SELECTION_X_DIM_SCALE * mpi_size;
+    dataset_dims[0] = (hsize_t)PARTIAL_NO_SELECTION_Y_DIM_SCALE * (hsize_t)mpi_size;
+    dataset_dims[1] = (hsize_t)PARTIAL_NO_SELECTION_X_DIM_SCALE * (hsize_t)mpi_size;
     max_dataset_dims[0] = H5S_UNLIMITED;
     max_dataset_dims[1] = H5S_UNLIMITED;
 
@@ -120,12 +120,12 @@ void test_partial_no_selection_coll_md_read(void)
      *
      * The ranks will write rows across the dataset.
      */
-    start[0] = PARTIAL_NO_SELECTION_Y_DIM_SCALE * mpi_rank;
+    start[0] = (hsize_t)PARTIAL_NO_SELECTION_Y_DIM_SCALE * (hsize_t)mpi_rank;
     start[1] = 0;
     stride[0] = PARTIAL_NO_SELECTION_Y_DIM_SCALE;
     stride[1] = PARTIAL_NO_SELECTION_X_DIM_SCALE;
     count[0] = 1;
-    count[1] = mpi_size;
+    count[1] = (hsize_t)mpi_size;
     block[0] = PARTIAL_NO_SELECTION_Y_DIM_SCALE;
     block[1] = PARTIAL_NO_SELECTION_X_DIM_SCALE;
 
@@ -405,7 +405,7 @@ void test_link_chunk_io_sort_chunk_issue(void)
     dataset_dims = HDmalloc(LINK_CHUNK_IO_SORT_CHUNK_ISSUE_DIMS * sizeof(*dataset_dims));
     VRFY((dataset_dims != NULL), "malloc succeeded");
 
-    dataset_dims[0] = LINK_CHUNK_IO_SORT_CHUNK_ISSUE_CHUNK_SIZE * mpi_size * LINK_CHUNK_IO_SORT_CHUNK_ISSUE_Y_DIM_SCALE;
+    dataset_dims[0] = (hsize_t)LINK_CHUNK_IO_SORT_CHUNK_ISSUE_CHUNK_SIZE * (hsize_t)mpi_size * (hsize_t)LINK_CHUNK_IO_SORT_CHUNK_ISSUE_Y_DIM_SCALE;
     max_dataset_dims[0] = H5S_UNLIMITED;
 
     fspace_id = H5Screate_simple(LINK_CHUNK_IO_SORT_CHUNK_ISSUE_DIMS, dataset_dims, max_dataset_dims);
@@ -428,8 +428,8 @@ void test_link_chunk_io_sort_chunk_issue(void)
      * The ranks will write rows across the dataset.
      */
     stride[0] = LINK_CHUNK_IO_SORT_CHUNK_ISSUE_CHUNK_SIZE;
-    count[0] = (dataset_dims[0] / LINK_CHUNK_IO_SORT_CHUNK_ISSUE_CHUNK_SIZE) / mpi_size;
-    start[0] = count[0] * mpi_rank;
+    count[0] = (dataset_dims[0] / LINK_CHUNK_IO_SORT_CHUNK_ISSUE_CHUNK_SIZE) / (hsize_t)mpi_size;
+    start[0] = count[0] * (hsize_t)mpi_rank;
     block[0] = LINK_CHUNK_IO_SORT_CHUNK_ISSUE_CHUNK_SIZE;
 
     VRFY((H5Sselect_hyperslab(fspace_id, H5S_SELECT_SET, start, stride, count, block) >= 0), "H5Sselect_hyperslab succeeded");
diff --git a/testpar/t_dset.c b/testpar/t_dset.c
index 87782d0..05baf3f 100644
--- a/testpar/t_dset.c
+++ b/testpar/t_dset.c
@@ -48,61 +48,61 @@ slab_set(int mpi_rank, int mpi_size, hsize_t start[], hsize_t count[],
     switch (mode) {
     case BYROW:
         /* Each process takes a slabs of rows. */
-        block[0] = dim0 / mpi_size;
-        block[1] = dim1;
+        block[0] = (hsize_t)(dim0 / mpi_size);
+        block[1] = (hsize_t)dim1;
         stride[0] = block[0];
         stride[1] = block[1];
         count[0] = 1;
         count[1] = 1;
-        start[0] = mpi_rank * block[0];
+        start[0] = (hsize_t)mpi_rank * block[0];
         start[1] = 0;
         if (VERBOSE_MED)
             HDprintf("slab_set BYROW\n");
         break;
     case BYCOL:
         /* Each process takes a block of columns. */
-        block[0] = dim0;
-        block[1] = dim1 / mpi_size;
+        block[0] = (hsize_t)dim0;
+        block[1] = (hsize_t)(dim1 / mpi_size);
         stride[0] = block[0];
         stride[1] = block[1];
         count[0] = 1;
         count[1] = 1;
         start[0] = 0;
-        start[1] = mpi_rank * block[1];
+        start[1] = (hsize_t)mpi_rank * block[1];
         if (VERBOSE_MED)
             HDprintf("slab_set BYCOL\n");
         break;
     case ZROW:
         /* Similar to BYROW except process 0 gets 0 row */
-        block[0] = (mpi_rank ? dim0 / mpi_size : 0);
-        block[1] = dim1;
+        block[0] = (hsize_t)(mpi_rank ? dim0 / mpi_size : 0);
+        block[1] = (hsize_t)dim1;
         stride[0] = (mpi_rank ? block[0] : 1); /* avoid setting stride to 0 */
         stride[1] = block[1];
         count[0] = 1;
         count[1] = 1;
-        start[0] = (mpi_rank ? mpi_rank * block[0] : 0);
+        start[0] = (hsize_t)(mpi_rank ? (hsize_t)mpi_rank * block[0] : 0);
         start[1] = 0;
         if (VERBOSE_MED)
             HDprintf("slab_set ZROW\n");
         break;
     case ZCOL:
         /* Similar to BYCOL except process 0 gets 0 column */
-        block[0] = dim0;
-        block[1] = (mpi_rank ? dim1 / mpi_size : 0);
+        block[0] = (hsize_t)dim0;
+        block[1] = (hsize_t)(mpi_rank ? dim1 / mpi_size : 0);
         stride[0] = block[0];
         stride[1] = (mpi_rank ? block[1] : 1); /* avoid setting stride to 0 */
         count[0] = 1;
         count[1] = 1;
         start[0] = 0;
-        start[1] = (mpi_rank ? mpi_rank * block[1] : 0);
+        start[1] = (hsize_t)(mpi_rank ? (hsize_t)mpi_rank * block[1] : 0);
         if (VERBOSE_MED)
             HDprintf("slab_set ZCOL\n");
         break;
     default:
         /* Unknown mode.  Set it to cover the whole dataset. */
         HDprintf("unknown slab_set mode (%d)\n", mode);
-        block[0] = dim0;
-        block[1] = dim1;
+        block[0] = (hsize_t)dim0;
+        block[1] = (hsize_t)dim1;
         stride[0] = block[0];
         stride[1] = block[1];
         count[0] = 1;
@@ -308,7 +308,7 @@ dataset_writeInd(void)
     MPI_Comm_rank(MPI_COMM_WORLD,&mpi_rank);
 
     /* allocate memory for data buffer */
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 HDmalloc succeeded");
 
     /* ----------------------------------------
@@ -332,8 +332,8 @@ dataset_writeInd(void)
      * and the slabs local to the MPI process.
      * ------------------------------------------- */
     /* setup dimensionality object */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     sid = H5Screate_simple (RANK, dims, NULL);
     VRFY((sid >= 0), "H5Screate_simple succeeded");
 
@@ -453,9 +453,9 @@ dataset_readInd(void)
     MPI_Comm_rank(MPI_COMM_WORLD,&mpi_rank);
 
     /* allocate memory for data buffer */
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 HDmalloc succeeded");
-    data_origin1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_origin1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_origin1 != NULL), "data_origin1 HDmalloc succeeded");
 
     /* setup file access template */
@@ -583,12 +583,12 @@ dataset_writeAll(void)
     MPI_Comm_rank(MPI_COMM_WORLD,&mpi_rank);
 
     /* set up the coords array selection */
-    num_points = dim1;
-    coords = (hsize_t *)HDmalloc(dim1 * RANK * sizeof(hsize_t));
+    num_points = (size_t)dim1;
+    coords = (hsize_t *)HDmalloc((size_t)dim1 * (size_t)RANK * sizeof(hsize_t));
     VRFY((coords != NULL), "coords malloc succeeded");
 
     /* allocate memory for data buffer */
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 HDmalloc succeeded");
 
     /* -------------------
@@ -612,8 +612,8 @@ dataset_writeAll(void)
      * and create the dataset
      * ------------------------- */
     /* setup 2-D dimensionality object */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     sid = H5Screate_simple (RANK, dims, NULL);
     VRFY((sid >= 0), "H5Screate_simple succeeded");
 
@@ -914,16 +914,16 @@ dataset_writeAll(void)
 
 
     if(data_array1) free(data_array1);
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 malloc succeeded");
 
     block[0] = 1;
-    block[1] = dim1;
+    block[1] = (hsize_t)dim1;
     stride[0] = 1;
-    stride[1] = dim1;
+    stride[1] = (hsize_t)dim1;
     count[0] = 1;
     count[1] = 1;
-    start[0] = dim0/mpi_size * mpi_rank;
+    start[0] = (hsize_t)(dim0/mpi_size * mpi_rank);
     start[1] = 0;
 
     dataset_fill(start, block, data_array1);
@@ -970,7 +970,7 @@ dataset_writeAll(void)
 
     /* Dataset6: point selection in File - Point selection in Memory*/
     /* create a file dataspace independently */
-    start[0] = dim0/mpi_size * mpi_rank;
+    start[0] = (hsize_t)(dim0/mpi_size * mpi_rank);
     start[1] = 0;
     point_set (start, count, stride, block, num_points, coords, OUT_OF_ORDER);
     file_dataspace = H5Dget_space (dataset6);
@@ -1008,7 +1008,7 @@ dataset_writeAll(void)
 
     /* Dataset7: point selection in File - All selection in Memory*/
     /* create a file dataspace independently */
-    start[0] = dim0/mpi_size * mpi_rank;
+    start[0] = (hsize_t)(dim0/mpi_size * mpi_rank);
     start[1] = 0;
     point_set (start, count, stride, block, num_points, coords, IN_ORDER);
     file_dataspace = H5Dget_space (dataset7);
@@ -1114,14 +1114,14 @@ dataset_readAll(void)
     MPI_Comm_rank(MPI_COMM_WORLD,&mpi_rank);
 
     /* set up the coords array selection */
-    num_points = dim1;
-    coords = (hsize_t *)HDmalloc(dim0 * dim1 * RANK * sizeof(hsize_t));
+    num_points = (size_t)dim1;
+    coords = (hsize_t *)HDmalloc((size_t)dim0 * (size_t)dim1 * (size_t)RANK * sizeof(hsize_t));
     VRFY((coords != NULL), "coords malloc succeeded");
 
     /* allocate memory for data buffer */
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 HDmalloc succeeded");
-    data_origin1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_origin1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_origin1 != NULL), "data_origin1 HDmalloc succeeded");
 
     /* -------------------
@@ -1299,18 +1299,18 @@ dataset_readAll(void)
 
     if(data_array1) free(data_array1);
     if(data_origin1) free(data_origin1);
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 malloc succeeded");
-    data_origin1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_origin1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_origin1 != NULL), "data_origin1 malloc succeeded");
 
     block[0] = 1;
-    block[1] = dim1;
+    block[1] = (hsize_t)dim1;
     stride[0] = 1;
-    stride[1] = dim1;
+    stride[1] = (hsize_t)dim1;
     count[0] = 1;
     count[1] = 1;
-    start[0] = dim0/mpi_size * mpi_rank;
+    start[0] = (hsize_t)(dim0/mpi_size * mpi_rank);
     start[1] = 0;
 
     dataset_fill(start, block, data_origin1);
@@ -1361,12 +1361,12 @@ dataset_readAll(void)
 
 
     if(data_array1) free(data_array1);
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 malloc succeeded");
 
     /* Dataset6: point selection in File - Point selection in Memory*/
     /* create a file dataspace independently */
-    start[0] = dim0/mpi_size * mpi_rank;
+    start[0] = (hsize_t)(dim0/mpi_size * mpi_rank);
     start[1] = 0;
     point_set (start, count, stride, block, num_points, coords, IN_ORDER);
     file_dataspace = H5Dget_space (dataset6);
@@ -1406,7 +1406,7 @@ dataset_readAll(void)
     H5Pclose(xfer_plist);
 
     if(data_array1) free(data_array1);
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 malloc succeeded");
 
     /* Dataset7: point selection in memory - All selection in file*/
@@ -1416,12 +1416,12 @@ dataset_readAll(void)
     ret = H5Sselect_all(file_dataspace);
     VRFY((ret >= 0), "H5Sselect_all succeeded");
 
-    num_points = dim0 * dim1;
+    H5_CHECKED_ASSIGN(num_points, size_t, dim0 * dim1, int);
     k=0;
     for (i=0 ; i<dim0; i++) {
         for (j=0 ; j<dim1; j++) {
-            coords[k++] = i;
-            coords[k++] = j;
+            coords[k++] = (hsize_t)i;
+            coords[k++] = (hsize_t)j;
         }
     }
     mem_dataspace = H5Dget_space (dataset7);
@@ -1444,7 +1444,7 @@ dataset_readAll(void)
                   xfer_plist, data_array1);
     VRFY((ret >= 0), "H5Dread dataset7 succeeded");
 
-    start[0] = dim0/mpi_size * mpi_rank;
+    start[0] = (hsize_t)(dim0/mpi_size * mpi_rank);
     start[1] = 0;
     ret = dataset_vrfy(start, count, stride, block, data_array1+(dim0/mpi_size * dim1 * mpi_rank), data_origin1);
     if(ret) nerrors++;
@@ -1527,11 +1527,11 @@ extend_writeInd(void)
     MPI_Comm_rank(MPI_COMM_WORLD,&mpi_rank);
 
     /* setup chunk-size. Make sure sizes are > 0 */
-    chunk_dims[0] = chunkdim0;
-    chunk_dims[1] = chunkdim1;
+    chunk_dims[0] = (hsize_t)chunkdim0;
+    chunk_dims[1] = (hsize_t)chunkdim1;
 
     /* allocate memory for data buffer */
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 HDmalloc succeeded");
 
     /* -------------------
@@ -1618,8 +1618,8 @@ extend_writeInd(void)
     VRFY((mem_dataspace >= 0), "");
 
     /* Extend its current dim sizes before writing */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     ret = H5Dset_extent(dataset1, dims);
     VRFY((ret >= 0), "H5Dset_extent succeeded");
 
@@ -1678,8 +1678,8 @@ extend_writeInd(void)
     H5Sclose(file_dataspace);
 
     /* Extend dataset2 and try again.  Should succeed. */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     ret = H5Dset_extent(dataset2, dims);
     VRFY((ret >= 0), "H5Dset_extent succeeded");
 
@@ -1840,7 +1840,7 @@ extend_writeInd2(void)
      * Write to the second half of the dataset
      * -------------------------*/
     for (i=0; i<(int)orig_size; i++)
-        written[i] = orig_size + i;
+        written[i] = (int)orig_size + i;
     MESG("data array re-initialized");
     if(VERBOSE_MED) {
     MESG("writing at offset 10: ");
@@ -1915,11 +1915,11 @@ extend_readInd(void)
     MPI_Comm_rank(MPI_COMM_WORLD,&mpi_rank);
 
     /* allocate memory for data buffer */
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 HDmalloc succeeded");
-    data_array2 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array2 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array2 != NULL), "data_array2 HDmalloc succeeded");
-    data_origin1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_origin1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_origin1 != NULL), "data_origin1 HDmalloc succeeded");
 
     /* -------------------
@@ -2098,11 +2098,11 @@ extend_writeAll(void)
     MPI_Comm_rank(MPI_COMM_WORLD,&mpi_rank);
 
     /* setup chunk-size. Make sure sizes are > 0 */
-    chunk_dims[0] = chunkdim0;
-    chunk_dims[1] = chunkdim1;
+    chunk_dims[0] = (hsize_t)chunkdim0;
+    chunk_dims[1] = (hsize_t)chunkdim1;
 
     /* allocate memory for data buffer */
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 HDmalloc succeeded");
 
     /* -------------------
@@ -2189,8 +2189,8 @@ extend_writeAll(void)
     VRFY((mem_dataspace >= 0), "");
 
     /* Extend its current dim sizes before writing */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     ret = H5Dset_extent(dataset1, dims);
     VRFY((ret >= 0), "H5Dset_extent succeeded");
 
@@ -2272,8 +2272,8 @@ extend_writeAll(void)
     H5Sclose(file_dataspace);
 
     /* Extend dataset2 and try again.  Should succeed. */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     ret = H5Dset_extent(dataset2, dims);
     VRFY((ret >= 0), "H5Dset_extent succeeded");
 
@@ -2345,11 +2345,11 @@ extend_readAll(void)
     MPI_Comm_rank(MPI_COMM_WORLD,&mpi_rank);
 
     /* allocate memory for data buffer */
-    data_array1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array1 != NULL), "data_array1 HDmalloc succeeded");
-    data_array2 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_array2 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_array2 != NULL), "data_array2 HDmalloc succeeded");
-    data_origin1 = (DATATYPE *)HDmalloc(dim0*dim1*sizeof(DATATYPE));
+    data_origin1 = (DATATYPE *)HDmalloc((size_t)dim0*(size_t)dim1*sizeof(DATATYPE));
     VRFY((data_origin1 != NULL), "data_origin1 HDmalloc succeeded");
 
     /* -------------------
@@ -2517,7 +2517,7 @@ compress_readAll(void)
     hid_t dataspace;        /* Dataspace ID */
     hid_t dataset;        /* Dataset ID */
     int rank=1;                 /* Dataspace rank */
-    hsize_t dim=dim0;           /* Dataspace dimensions */
+    hsize_t dim=(hsize_t)dim0;  /* Dataspace dimensions */
     unsigned u;                 /* Local index variable */
     unsigned    chunk_opts;         /* Chunk options */
     unsigned    disable_partial_chunk_filters; /* Whether filters are disabled on partial chunks */
@@ -2545,7 +2545,7 @@ compress_readAll(void)
 
     /* Initialize data buffers */
     for(u=0; u<dim;u++)
-        data_orig[u]=u;
+        data_orig[u]=(int)u;
 
     /* Run test both with and without filters disabled on partial chunks */
     for(disable_partial_chunk_filters = 0; disable_partial_chunk_filters <= 1;
@@ -2729,8 +2729,8 @@ none_selection_chunk(void)
     MPI_Comm_rank(MPI_COMM_WORLD,&mpi_rank);
 
     /* setup chunk-size. Make sure sizes are > 0 */
-    chunk_dims[0] = chunkdim0;
-    chunk_dims[1] = chunkdim1;
+    chunk_dims[0] = (hsize_t)chunkdim0;
+    chunk_dims[1] = (hsize_t)chunkdim1;
 
     /* -------------------
      * START AN HDF5 FILE
@@ -2760,8 +2760,8 @@ none_selection_chunk(void)
     VRFY((ret >= 0), "H5Pset_chunk succeeded");
 
     /* setup dimensionality object */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     sid = H5Screate_simple(RANK, dims, NULL);
     VRFY((sid >= 0), "H5Screate_simple succeeded");
 
@@ -3038,8 +3038,8 @@ test_actual_io_mode(int selection_mode) {
     VRFY((fid >= 0), "H5Fcreate succeeded");
 
     /* Create the basic Space */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     sid = H5Screate_simple (RANK, dims, NULL);
     VRFY((sid >= 0), "H5Screate_simple succeeded");
 
@@ -3050,7 +3050,7 @@ test_actual_io_mode(int selection_mode) {
     /* If we are not testing contiguous datasets */
     if(is_chunked) {
         /* Set up chunk information.  */
-        chunk_dims[0] = dims[0]/mpi_size;
+        chunk_dims[0] = dims[0]/(hsize_t)mpi_size;
         chunk_dims[1] = dims[1];
         ret = H5Pset_chunk(dcpl, 2, chunk_dims);
         VRFY((ret >= 0),"chunk creation property list succeeded");
@@ -3116,14 +3116,14 @@ test_actual_io_mode(int selection_mode) {
                  slab_set(mpi_rank, mpi_size, start, count, stride, block, BYCOL);
             } else {
                 /* Select the first and the nth chunk in the nth column */
-                block[0] = dim0 / mpi_size;
-                block[1] = dim1 / mpi_size;
+                block[0] = (hsize_t)(dim0 / mpi_size);
+                block[1] = (hsize_t)(dim1 / mpi_size);
                 count[0] = 2;
                 count[1] = 1;
-                stride[0] = mpi_rank * block[0];
+                stride[0] = (hsize_t)mpi_rank * block[0];
                 stride[1] = 1;
                 start[0] = 0;
-                start[1] = mpi_rank*block[1];
+                start[1] = (hsize_t)mpi_rank*block[1];
             }
 
             test_name = "Multi Chunk - Mixed";
@@ -3154,17 +3154,17 @@ test_actual_io_mode(int selection_mode) {
             if(mpi_rank == 0) {
                  /* Select the first chunk in the first column */
                  slab_set(mpi_rank, mpi_size, start, count, stride, block, BYCOL);
-                 block[0] = block[0] / mpi_size;
+                 block[0] = block[0] / (hsize_t)mpi_size;
             } else {
                 /* Select the first and the nth chunk in the nth column */
-                block[0] = dim0 / mpi_size;
-                block[1] = dim1 / mpi_size;
+                block[0] = (hsize_t)(dim0 / mpi_size);
+                block[1] = (hsize_t)(dim1 / mpi_size);
                 count[0] = 2;
                 count[1] = 1;
-                stride[0] = mpi_rank * block[0];
+                stride[0] = (hsize_t)mpi_rank * block[0];
                 stride[1] = 1;
                 start[0] = 0;
-                start[1] = mpi_rank*block[1];
+                start[1] = (hsize_t)mpi_rank*block[1];
             }
 
             /* If the testname was not already set by the RESET case */
@@ -3237,7 +3237,7 @@ test_actual_io_mode(int selection_mode) {
     length = dim0 * dim1;
 
     /* Allocate and initialize the buffer */
-    buffer = (int *)HDmalloc(sizeof(int) * length);
+    buffer = (int *)HDmalloc(sizeof(int) * (size_t)length);
     VRFY((buffer != NULL), "HDmalloc of buffer succeeded");
     for(i = 0; i < length; i++)
         buffer[i] = i;
@@ -3566,8 +3566,8 @@ test_no_collective_cause_mode(int selection_mode)
             dims[1] = COL_FACTOR * 6;
         }
         else {
-            dims[0] = dim0;
-            dims[1] = dim1;
+            dims[0] = (hsize_t)dim0;
+            dims[1] = (hsize_t)dim1;
         }
         sid = H5Screate_simple (RANK, dims, NULL);
         VRFY((sid >= 0), "H5Screate_simple succeeded");
@@ -3589,7 +3589,7 @@ test_no_collective_cause_mode(int selection_mode)
     /* If we are not testing contiguous datasets */
     if(is_chunked) {
         /* Set up chunk information.  */
-        chunk_dims[0] = dims[0]/mpi_size;
+        chunk_dims[0] = dims[0]/(hsize_t)mpi_size;
         chunk_dims[1] = dims[1];
         ret = H5Pset_chunk(dcpl, 2, chunk_dims);
         VRFY((ret >= 0),"chunk creation property list succeeded");
@@ -3670,10 +3670,10 @@ test_no_collective_cause_mode(int selection_mode)
     }
 
     /* Get the number of elements in the selection */
-    length = dims[0] * dims[1];
+    H5_CHECKED_ASSIGN(length, int, dims[0] * dims[1], uint64_t);
 
     /* Allocate and initialize the buffer */
-    buffer = (int *)HDmalloc(sizeof(int) * length);
+    buffer = (int *)HDmalloc(sizeof(int) * (size_t)length);
     VRFY((buffer != NULL), "HDmalloc of buffer succeeded");
     for(i = 0; i < length; i++)
         buffer[i] = i;
@@ -3864,8 +3864,8 @@ test_no_collective_cause_mode_filter(int selection_mode)
     }
 
     /* Create the basic Space */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     sid = H5Screate_simple (RANK, dims, NULL);
     VRFY((sid >= 0), "H5Screate_simple succeeded");
 
@@ -3883,7 +3883,7 @@ test_no_collective_cause_mode_filter(int selection_mode)
     /* If we are not testing contiguous datasets */
     if(is_chunked) {
         /* Set up chunk information.  */
-        chunk_dims[0] = dims[0]/mpi_size;
+        chunk_dims[0] = dims[0]/(hsize_t)mpi_size;
         chunk_dims[1] = dims[1];
         ret = H5Pset_chunk(dcpl, 2, chunk_dims);
         VRFY((ret >= 0),"chunk creation property list succeeded");
@@ -3913,7 +3913,7 @@ test_no_collective_cause_mode_filter(int selection_mode)
     length = dim0 * dim1;
 
     /* Allocate and initialize the buffer */
-    buffer = (int *)HDmalloc(sizeof(int) * length);
+    buffer = (int *)HDmalloc(sizeof(int) * (size_t)length);
     VRFY((buffer != NULL), "HDmalloc of buffer succeeded");
     for(i = 0; i < length; i++)
         buffer[i] = i;
@@ -4099,10 +4099,10 @@ dataset_atomicity(void)
 
     buf_size = dim0 * dim1;
     /* allocate memory for data buffer */
-    write_buf = (int *)HDcalloc(buf_size, sizeof(int));
+    write_buf = (int *)HDcalloc((size_t)buf_size, sizeof(int));
     VRFY((write_buf != NULL), "write_buf HDcalloc succeeded");
     /* allocate memory for data buffer */
-    read_buf = (int *)HDcalloc(buf_size, sizeof(int));
+    read_buf = (int *)HDcalloc((size_t)buf_size, sizeof(int));
     VRFY((read_buf != NULL), "read_buf HDcalloc succeeded");
 
     /* setup file access template */
@@ -4118,8 +4118,8 @@ dataset_atomicity(void)
     VRFY((ret >= 0), "H5Pclose succeeded");
 
     /* setup dimensionality object */
-    dims[0] = dim0;
-    dims[1] = dim1;
+    dims[0] = (hsize_t)dim0;
+    dims[1] = (hsize_t)dim1;
     sid = H5Screate_simple (RANK, dims, NULL);
     VRFY((sid >= 0), "H5Screate_simple succeeded");
 
@@ -4257,10 +4257,10 @@ dataset_atomicity(void)
     VRFY((dataset2 >= 0), "H5Dopen2 succeeded");
 
     /* allocate memory for data buffer */
-    write_buf = (int *)HDcalloc(buf_size, sizeof(int));
+    write_buf = (int *)HDcalloc((size_t)buf_size, sizeof(int));
     VRFY((write_buf != NULL), "write_buf HDcalloc succeeded");
     /* allocate memory for data buffer */
-    read_buf = (int *)HDcalloc(buf_size, sizeof(int));
+    read_buf = (int *)HDcalloc((size_t)buf_size, sizeof(int));
     VRFY((read_buf != NULL), "read_buf HDcalloc succeeded");
 
     for (i=0 ; i<buf_size ; i++) {
@@ -4277,12 +4277,12 @@ dataset_atomicity(void)
     VRFY((atomicity == TRUE), "atomcity set failed");
 
 
-    block[0] = dim0/mpi_size - 1;
-    block[1] = dim1/mpi_size - 1;
+    block[0] = (hsize_t)(dim0/mpi_size - 1);
+    block[1] = (hsize_t)(dim1/mpi_size - 1);
     stride[0] = block[0] + 1;
     stride[1] = block[1] + 1;
-    count[0] = mpi_size;
-    count[1] = mpi_size;
+    count[0] = (hsize_t)mpi_size;
+    count[1] = (hsize_t)mpi_size;
     start[0] = 0;
     start[1] = 0;
 
@@ -4338,19 +4338,19 @@ dataset_atomicity(void)
         compare = 5;
 
         for (i=0 ; i<dim0 ; i++) {
-            if (i >= mpi_rank*(block[0]+1)) {
+            if ((hsize_t)i >= (hsize_t)mpi_rank*(block[0]+1)) {
                 break;
             }
-            if ((i+1)%(block[0]+1)==0) {
+            if (((hsize_t)i+1)%(block[0]+1)==0) {
                 k += dim1;
                 continue;
             }
             for (j=0 ; j<dim1 ; j++) {
-                if (j >= mpi_rank*(block[1]+1)) {
-                    k += dim1 - mpi_rank*(block[1]+1);
+                if ((hsize_t)j >= (hsize_t)mpi_rank*(block[1]+1)) {
+                    H5_CHECKED_ASSIGN(k, int, (hsize_t)dim1 - (hsize_t)mpi_rank*(block[1]+1), hsize_t);
                     break;
                 }
-                if ((j+1)%(block[1]+1)==0) {
+                if (((hsize_t)j+1)%(block[1]+1)==0) {
                     k++;
                     continue;
                 }
diff --git a/testpar/t_file.c b/testpar/t_file.c
index 99ac189..6183b8d 100644
--- a/testpar/t_file.c
+++ b/testpar/t_file.c
@@ -471,19 +471,19 @@ create_file(const char *filename, hid_t fcpl, hid_t fapl, int metadata_write_str
     grp_id = H5Gcreate2(file_id, "GROUP", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
     VRFY((grp_id >= 0), "");
 
-    dims[0] = ROW_FACTOR*mpi_size;
-    dims[1] = COL_FACTOR*mpi_size;
+    dims[0] = (hsize_t)(ROW_FACTOR*mpi_size);
+    dims[1] = (hsize_t)(COL_FACTOR*mpi_size);
     sid = H5Screate_simple (RANK, dims, NULL);
     VRFY((sid >= 0), "H5Screate_simple succeeded");
 
     /* Each process takes a slabs of rows. */
-    block[0] = dims[0]/mpi_size;
+    block[0] = dims[0]/(hsize_t)mpi_size;
     block[1] = dims[1];
     stride[0] = block[0];
     stride[1] = block[1];
     count[0] = 1;
     count[1] = 1;
-    start[0] = mpi_rank*block[0];
+    start[0] = (hsize_t)mpi_rank*block[0];
     start[1] = 0;
 
     num_elements = block[0] * block[1];
@@ -632,17 +632,17 @@ open_file(const char *filename, hid_t fapl, int metadata_write_strategy,
     grp_id = H5Gopen2(file_id, "GROUP", H5P_DEFAULT);
     VRFY((grp_id >= 0), "");
 
-    dims[0] = ROW_FACTOR*mpi_size;
-    dims[1] = COL_FACTOR*mpi_size;
+    dims[0] = (hsize_t)(ROW_FACTOR*mpi_size);
+    dims[1] = (hsize_t)(COL_FACTOR*mpi_size);
 
     /* Each process takes a slabs of rows. */
-    block[0] = dims[0]/mpi_size;
+    block[0] = dims[0]/(hsize_t)mpi_size;
     block[1] = dims[1];
     stride[0] = block[0];
     stride[1] = block[1];
     count[0] = 1;
     count[1] = 1;
-    start[0] = mpi_rank*block[0];
+    start[0] = (hsize_t)mpi_rank*block[0];
     start[1] = 0;
 
     num_elements = block[0] * block[1];
diff --git a/testpar/t_filter_read.c b/testpar/t_filter_read.c
index cabb51e..7b0e677 100644
--- a/testpar/t_filter_read.c
+++ b/testpar/t_filter_read.c
@@ -74,10 +74,10 @@ filter_read_internal(const char *filename, hid_t dcpl,
     hs_size[0] = size[0] = HS_DIM1;
     hs_size[1] = HS_DIM2;
 
-    size[1] = hs_size[1] * mpi_size;
+    size[1] = hs_size[1] * (hsize_t)mpi_size;
 
     hs_offset[0] = 0;
-    hs_offset[1] = hs_size[1] * mpi_rank;
+    hs_offset[1] = hs_size[1] * (hsize_t)mpi_rank;
 
     /* Create the data space */
     sid = H5Screate_simple(2, size, NULL);
diff --git a/testpar/t_mdset.c b/testpar/t_mdset.c
index ee868ee..6cdb0af7 100644
--- a/testpar/t_mdset.c
+++ b/testpar/t_mdset.c
@@ -157,11 +157,12 @@ void multiple_dset_write(void)
     ndatasets = pt->count;
 
     size = get_size();
+    H5_CHECK_OVERFLOW(size, int, size_t);
 
     MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
     MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);
 
-    outme = HDmalloc((size_t)(size * size * sizeof(double)));
+    outme = HDmalloc((size_t)size * (size_t)size * sizeof(double));
     VRFY((outme != NULL), "HDmalloc succeeded for outme");
 
     plist = create_faccess_plist(MPI_COMM_WORLD, MPI_INFO_NULL, facc_type);
@@ -238,15 +239,15 @@ void compact_dataset(void)
     size = get_size();
 
     for(i = 0; i < DIM; i++ )
-        file_dims[i] = size;
+        file_dims[i] = (hsize_t)size;
 
     MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
     MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);
 
-    outme = HDmalloc((size_t)(size * size * sizeof(double)));
+    outme = HDmalloc((size_t)((size_t)size * (size_t)size * sizeof(double)));
     VRFY((outme != NULL), "HDmalloc succeeded for outme");
 
-    inme = HDmalloc((size_t)(size * size * sizeof(double)));
+    inme = HDmalloc((size_t)size * (size_t)size * sizeof(double));
     VRFY((outme != NULL), "HDmalloc succeeded for inme");
 
     filename = GetTestParameters();
@@ -363,7 +364,7 @@ void null_dataset(void)
     hid_t    iof, plist, dxpl, dataset, attr, sid;
     unsigned uval=2;    /* Buffer for writing to dataset */
     int      val=1;          /* Buffer for writing to attribute */
-    int      nelem;
+    hssize_t nelem;
     char     dname[]="dataset";
     char     attr_name[]="attribute";
     herr_t   ret;
@@ -627,7 +628,7 @@ void dataset_fillvalue(void)
 
     /* Set the dataset dimension to be one row more than number of processes */
     /* and calculate the actual dataset size. */
-    dset_dims[0]=mpi_size+1;
+    dset_dims[0]=(hsize_t)(mpi_size+1);
     dset_size=dset_dims[0]*dset_dims[1]*dset_dims[2]*dset_dims[3];
 
     /* Allocate space for the buffers */
@@ -720,7 +721,7 @@ void dataset_fillvalue(void)
      * Each process writes 1 row of data. Thus last row is not written.
      */
     /* Create hyperslabs in memory and file dataspaces */
-    req_start[0]=mpi_rank;
+    req_start[0]=(hsize_t)mpi_rank;
     ret = H5Sselect_hyperslab(filespace, H5S_SELECT_SET, req_start, NULL, req_count, NULL);
     VRFY((ret >= 0), "H5Sselect_hyperslab succeeded on memory dataspace");
     ret = H5Sselect_hyperslab(memspace, H5S_SELECT_SET, req_start, NULL, req_count, NULL);
@@ -878,7 +879,7 @@ void collective_group_write(void)
     chunk_size[0] =(hsize_t)(size / 2);
     chunk_size[1] =(hsize_t)(size / 2);
 
-    outme = HDmalloc((size_t)(size * size * sizeof(DATATYPE)));
+    outme = HDmalloc((size_t)size * (size_t)size * sizeof(DATATYPE));
     VRFY((outme != NULL), "HDmalloc succeeded for outme");
 
     plist = create_faccess_plist(MPI_COMM_WORLD, MPI_INFO_NULL, facc_type);
@@ -1002,10 +1003,10 @@ group_dataset_read(hid_t fid, int mpi_rank, int m)
 
     size = get_size();
 
-    indata =(DATATYPE*)HDmalloc((size_t)(size * size * sizeof(DATATYPE)));
+    indata =(DATATYPE*)HDmalloc((size_t)size * (size_t)size * sizeof(DATATYPE));
     VRFY((indata != NULL), "HDmalloc succeeded for indata");
 
-    outdata =(DATATYPE*)HDmalloc((size_t)(size * size * sizeof(DATATYPE)));
+    outdata =(DATATYPE*)HDmalloc((size_t)size * (size_t)size * sizeof(DATATYPE));
     VRFY((outdata != NULL), "HDmalloc succeeded for outdata");
 
     /* open every group under root group. */
@@ -1173,7 +1174,7 @@ write_dataset(hid_t memspace, hid_t filespace, hid_t gid)
 
     size = get_size();
 
-    outme = HDmalloc((size_t)(size * size * sizeof(double)));
+    outme = HDmalloc((size_t)size * (size_t)size * sizeof(double));
     VRFY((outme != NULL), "HDmalloc succeeded for outme");
 
     for(n = 0; n < NDATASET; n++) {
@@ -1333,10 +1334,10 @@ read_dataset(hid_t memspace, hid_t filespace, hid_t gid)
 
     size = get_size();
 
-    indata =(DATATYPE*)HDmalloc((size_t)(size * size * sizeof(DATATYPE)));
+    indata =(DATATYPE*)HDmalloc((size_t)size * (size_t)size * sizeof(DATATYPE));
     VRFY((indata != NULL), "HDmalloc succeeded for indata");
 
-    outdata =(DATATYPE*)HDmalloc((size_t)(size * size * sizeof(DATATYPE)));
+    outdata =(DATATYPE*)HDmalloc((size_t)size * (size_t)size * sizeof(DATATYPE));
     VRFY((outdata != NULL), "HDmalloc succeeded for outdata");
 
     for(n=0; n<NDATASET; n++) {
@@ -1490,8 +1491,8 @@ check_value(DATATYPE *indata, DATATYPE *outdata, int size)
 
     get_slab(chunk_origin, chunk_dims, count, NULL, size);
 
-    indata += chunk_origin[0]*size;
-    outdata += chunk_origin[0]*size;
+    indata += chunk_origin[0]*(hsize_t)size;
+    outdata += chunk_origin[0]*(hsize_t)size;
     for(i=chunk_origin[0]; i<(chunk_origin[0]+chunk_dims[0]); i++)
         for(j=chunk_origin[1]; j<(chunk_origin[1]+chunk_dims[1]); j++) {
             if(*indata != *outdata )
@@ -1524,15 +1525,15 @@ get_slab(hsize_t chunk_origin[], hsize_t chunk_dims[], hsize_t count[],
     MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);
 
     if(chunk_origin != NULL) {
-        chunk_origin[0] = mpi_rank *(size/mpi_size);
+        chunk_origin[0] = (hsize_t)mpi_rank * (hsize_t)(size/mpi_size);
         chunk_origin[1] = 0;
     }
     if(chunk_dims != NULL) {
-        chunk_dims[0]   = size/mpi_size;
-        chunk_dims[1]   = size;
+        chunk_dims[0]   = (hsize_t)(size/mpi_size);
+        chunk_dims[1]   = (hsize_t)size;
     }
     if(file_dims != NULL)
-        file_dims[0] = file_dims[1] = size;
+        file_dims[0] = file_dims[1] = (hsize_t)size;
     if(count != NULL)
         count[0] = count[1] = 1;
 }
diff --git a/testpar/t_mpi.c b/testpar/t_mpi.c
index fe78317..064fb57 100644
--- a/testpar/t_mpi.c
+++ b/testpar/t_mpi.c
@@ -302,8 +302,8 @@ static int test_mpio_gb_file(char *filename) {
                             "proc %d: write to mpi_off=%016llx, %lld\n",
                             mpi_rank, mpi_off, mpi_off);
                 /* set data to some trivial pattern for easy verification */
-                for (j = 0; j < MB; j++)
-                    *(buf + j) = (int8_t)(i * mpi_size + mpi_rank);
+                for (j = 0; j < MB; j++) 
+                    H5_CHECKED_ASSIGN(*(buf + j), int8_t, i * mpi_size + mpi_rank, int);
                 if (VERBOSE_MED)
                     HDfprintf(stdout,
                             "proc %d: writing %d bytes at offset %lld\n",
@@ -351,7 +351,7 @@ static int test_mpio_gb_file(char *filename) {
                 mrc = MPI_File_read_at(fh, mpi_off, buf, MB, MPI_BYTE,
                         &mpi_stat);
                 INFO((mrc == MPI_SUCCESS), "GB size file read");
-                expected = (int8_t)(i * mpi_size + (mpi_size - mpi_rank - 1));
+                H5_CHECKED_ASSIGN(expected, int8_t, i * mpi_size + (mpi_size - mpi_rank - 1), int);
                 vrfyerrs = 0;
                 for (j = 0; j < MB; j++) {
                     if ((*(buf + j) != expected)
@@ -526,7 +526,7 @@ static int test_mpio_1wMr(char *filename, int special_request) {
     * ==================================================*/
     irank = 0;
     for (i = 0; i < DIMSIZE; i++)
-        H5_CHECKED_ASSIGN(writedata[i], uint8_t, irank * DIMSIZE + i, int)
+         H5_CHECKED_ASSIGN(writedata[i], uint8_t, irank * DIMSIZE + i, int)
     mpi_off = irank * DIMSIZE;
 
     /* Only one process writes */
@@ -697,7 +697,7 @@ static int test_mpio_derived_dtype(char *filename) {
     MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
     retcode = 0;
     for (i = 0; i < 3; i++)
-        H5_CHECKED_ASSIGN(buf[i], int8_t, i + 1, int);
+        buf[i] = (char)(i + 1);
 
     if ((mpi_err = MPI_File_open(MPI_COMM_WORLD, filename,
             MPI_MODE_RDWR | MPI_MODE_CREATE, MPI_INFO_NULL, &fh))
diff --git a/testpar/t_prestart.c b/testpar/t_prestart.c
index d75e627..fc9d475 100644
--- a/testpar/t_prestart.c
+++ b/testpar/t_prestart.c
@@ -81,13 +81,13 @@ main (int argc, char **argv)
     VRFY((data_array != NULL), "data_array HDmalloc succeeded");
 
     /* Each process takes a slabs of rows. */
-    block[0] = dims[0]/mpi_size;
+    block[0] = dims[0]/(hsize_t)mpi_size;
     block[1] = dims[1];
     stride[0] = block[0];
     stride[1] = block[1];
     count[0] = 1;
     count[1] = 1;
-    start[0] = mpi_rank*block[0];
+    start[0] = (hsize_t)mpi_rank*block[0];
     start[1] = 0;
 
     ret = H5Sselect_hyperslab(sid, H5S_SELECT_SET, start, stride, count, block);
@@ -109,7 +109,7 @@ main (int argc, char **argv)
 	    if(*dataptr != mpi_rank+1) {
                 HDprintf("Dataset Verify failed at [%lu][%lu](row %lu, col %lu): expect %d, got %d\n",
                        (unsigned long)i, (unsigned long)j,
-                       (unsigned long)(i+start[0]), (unsigned long)(j+start[1]),
+                       (unsigned long)((hsize_t)i+start[0]), (unsigned long)((hsize_t)j+start[1]),
                        mpi_rank+1, *(dataptr));
                 nerrors ++;
             }
diff --git a/testpar/t_prop.c b/testpar/t_prop.c
index fd89c6a..62e4dde 100644
--- a/testpar/t_prop.c
+++ b/testpar/t_prop.c
@@ -53,7 +53,7 @@ test_encode_decode(hid_t orig_pl, int mpi_rank, int recv_proc)
         void *rbuf;
 
         MPI_Recv(&recv_size, 1, MPI_INT, 0, 123, MPI_COMM_WORLD, &status);
-        buf_size = recv_size;
+        buf_size = (size_t)recv_size;
         rbuf = (uint8_t *)HDmalloc(buf_size);
         MPI_Recv(rbuf, recv_size, MPI_BYTE, 0, 124, MPI_COMM_WORLD, &status);
 
diff --git a/testpar/t_pshutdown.c b/testpar/t_pshutdown.c
index def7071..ddbae9e 100644
--- a/testpar/t_pshutdown.c
+++ b/testpar/t_pshutdown.c
@@ -68,8 +68,8 @@ main (int argc, char **argv)
     grp_id = H5Gcreate2(file_id, "Group", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
     VRFY((grp_id >= 0), "H5Gcreate succeeded");
 
-    dims[0] = ROW_FACTOR*mpi_size;
-    dims[1] = COL_FACTOR*mpi_size;
+    dims[0] = (hsize_t)ROW_FACTOR*(hsize_t)mpi_size;
+    dims[1] = (hsize_t)COL_FACTOR*(hsize_t)mpi_size;
     sid = H5Screate_simple (RANK, dims, NULL);
     VRFY((sid >= 0), "H5Screate_simple succeeded");
 
@@ -81,13 +81,13 @@ main (int argc, char **argv)
     VRFY((data_array != NULL), "data_array HDmalloc succeeded");
 
     /* Each process takes a slabs of rows. */
-    block[0] = dims[0]/mpi_size;
+    block[0] = dims[0]/(hsize_t)mpi_size;
     block[1] = dims[1];
     stride[0] = block[0];
     stride[1] = block[1];
     count[0] = 1;
     count[1] = 1;
-    start[0] = mpi_rank*block[0];
+    start[0] = (hsize_t)mpi_rank*block[0];
     start[1] = 0;
 
     /* put some trivial data in the data_array */
diff --git a/testpar/t_span_tree.c b/testpar/t_span_tree.c
index c3cc7b5..e1a86a1 100644
--- a/testpar/t_span_tree.c
+++ b/testpar/t_span_tree.c
@@ -246,19 +246,19 @@ void coll_write_test(int chunk_factor)
    * Buffers' initialization.
    */
 
-  mdim1[0] = MSPACE1_DIM *mpi_size;
+  mdim1[0] = (hsize_t)(MSPACE1_DIM*mpi_size);
   mdim[0]  = MSPACE_DIM1;
-  mdim[1]  = MSPACE_DIM2*mpi_size;
+  mdim[1]  = (hsize_t)(MSPACE_DIM2*mpi_size);
   fsdim[0] = FSPACE_DIM1;
-  fsdim[1] = FSPACE_DIM2*mpi_size;
+  fsdim[1] = (hsize_t)(FSPACE_DIM2*mpi_size);
 
-  vector = (int*)HDmalloc(sizeof(int)*mdim1[0]*mpi_size);
-  matrix_out  = (int*)HDmalloc(sizeof(int)*mdim[0]*mdim[1]*mpi_size);
-  matrix_out1 = (int*)HDmalloc(sizeof(int)*mdim[0]*mdim[1]*mpi_size);
+  vector = (int*)HDmalloc(sizeof(int)*(size_t)mdim1[0]*(size_t)mpi_size);
+  matrix_out  = (int*)HDmalloc(sizeof(int)*(size_t)mdim[0]*(size_t)mdim[1]*(size_t)mpi_size);
+  matrix_out1 = (int*)HDmalloc(sizeof(int)*(size_t)mdim[0]*(size_t)mdim[1]*(size_t)mpi_size);
 
-  HDmemset(vector,0,sizeof(int)*mdim1[0]*mpi_size);
+  HDmemset(vector,0,sizeof(int)*(size_t)mdim1[0]*(size_t)mpi_size);
   vector[0] = vector[MSPACE1_DIM*mpi_size - 1] = -1;
-  for (i = 1; i < MSPACE1_DIM*mpi_size - 1; i++) vector[i] = i;
+  for (i = 1; i < MSPACE1_DIM*mpi_size - 1; i++) H5_CHECKED_ASSIGN(vector[i], int, i, unsigned);
 
   /* Grab file access property list */
   facc_plist = create_faccess_plist(comm, info, facc_type);
@@ -280,8 +280,8 @@ void coll_write_test(int chunk_factor)
   VRFY((ret >= 0),"Fill value creation property list succeeded");
 
   if(chunk_factor != 0) {
-    chunk_dims[0] = fsdim[0] / chunk_factor;
-    chunk_dims[1] = fsdim[1] / chunk_factor;
+    chunk_dims[0] = fsdim[0] / (hsize_t)chunk_factor;
+    chunk_dims[1] = fsdim[1] / (hsize_t)chunk_factor;
     ret = H5Pset_chunk(dcrt_plist, 2, chunk_dims);
     VRFY((ret >= 0),"chunk creation property list succeeded");
   }
@@ -317,7 +317,7 @@ void coll_write_test(int chunk_factor)
    */
 
   start[0]  = FHSTART0;
-  start[1]  = FHSTART1 + mpi_rank * FHSTRIDE1 * FHCOUNT1;
+  start[1]  = (hsize_t)(FHSTART1 + mpi_rank * FHSTRIDE1 * FHCOUNT1);
   stride[0] = FHSTRIDE0;
   stride[1] = FHSTRIDE1;
   count[0]  = FHCOUNT0;
@@ -338,7 +338,7 @@ void coll_write_test(int chunk_factor)
    */
 
   start[0]  = SHSTART0;
-  start[1]  = SHSTART1+SHCOUNT1*SHBLOCK1*mpi_rank;
+  start[1]  = (hsize_t)(SHSTART1+SHCOUNT1*SHBLOCK1*mpi_rank);
   stride[0] = SHSTRIDE0;
   stride[1] = SHSTRIDE1;
   count[0]  = SHCOUNT0;
@@ -476,7 +476,7 @@ void coll_write_test(int chunk_factor)
    *
    */
   start[0]  = RFFHSTART0;
-  start[1]  = RFFHSTART1+mpi_rank*RFFHCOUNT1;
+  start[1]  = (hsize_t)(RFFHSTART1+mpi_rank*RFFHCOUNT1);
   block[0]  = RFFHBLOCK0;
   block[1]  = RFFHBLOCK1;
   stride[0] = RFFHSTRIDE0;
@@ -503,7 +503,7 @@ void coll_write_test(int chunk_factor)
    */
 
   start[0] = RFSHSTART0;
-  start[1] = RFSHSTART1+RFSHCOUNT1*mpi_rank;
+  start[1] = (hsize_t)(RFSHSTART1+RFSHCOUNT1*mpi_rank);
   block[0] = RFSHBLOCK0;
   block[1] = RFSHBLOCK1;
   stride[0] = RFSHSTRIDE0;
@@ -542,7 +542,7 @@ void coll_write_test(int chunk_factor)
 
 
   start[0]  = RMFHSTART0;
-  start[1]  = RMFHSTART1+mpi_rank*RMFHCOUNT1;
+  start[1]  = (hsize_t)(RMFHSTART1+mpi_rank*RMFHCOUNT1);
   block[0]  = RMFHBLOCK0;
   block[1]  = RMFHBLOCK1;
   stride[0] = RMFHSTRIDE0;
@@ -565,7 +565,7 @@ void coll_write_test(int chunk_factor)
    *
    */
   start[0]  = RMSHSTART0;
-  start[1]  = RMSHSTART1+mpi_rank*RMSHCOUNT1;
+  start[1]  = (hsize_t)(RMSHSTART1+mpi_rank*RMSHCOUNT1);
   block[0]  = RMSHBLOCK0;
   block[1]  = RMSHBLOCK1;
   stride[0] = RMSHSTRIDE0;
@@ -580,8 +580,8 @@ void coll_write_test(int chunk_factor)
    * Initialize data buffer.
    */
 
-  HDmemset(matrix_out,0,sizeof(int)*MSPACE_DIM1*MSPACE_DIM2*mpi_size);
-  HDmemset(matrix_out1,0,sizeof(int)*MSPACE_DIM1*MSPACE_DIM2*mpi_size);
+  HDmemset(matrix_out,0,sizeof(int)*(size_t)MSPACE_DIM1*(size_t)MSPACE_DIM2*(size_t)mpi_size);
+  HDmemset(matrix_out1,0,sizeof(int)*(size_t)MSPACE_DIM1*(size_t)MSPACE_DIM2*(size_t)mpi_size);
   /*
    * Read data back to the buffer matrix_out.
    */
@@ -704,9 +704,9 @@ coll_read_test(void)
   /* Initialize the buffer */
 
   mdim[0] = MSPACE_DIM1;
-  mdim[1] = MSPACE_DIM2*mpi_size;
-  matrix_out =(int*)HDmalloc(sizeof(int)*MSPACE_DIM1*MSPACE_DIM2*mpi_size);
-  matrix_out1=(int*)HDmalloc(sizeof(int)*MSPACE_DIM1*MSPACE_DIM2*mpi_size);
+  mdim[1] = (hsize_t)(MSPACE_DIM2*mpi_size);
+  matrix_out =(int*)HDmalloc(sizeof(int)*(size_t)MSPACE_DIM1*(size_t)MSPACE_DIM2*(size_t)mpi_size);
+  matrix_out1=(int*)HDmalloc(sizeof(int)*(size_t)MSPACE_DIM1*(size_t)MSPACE_DIM2*(size_t)mpi_size);
 
   /*** For testing collective hyperslab selection read ***/
 
@@ -741,7 +741,7 @@ coll_read_test(void)
    *
    */
   start[0]  = RFFHSTART0;
-  start[1]  = RFFHSTART1+mpi_rank*RFFHCOUNT1;
+  start[1]  = (hsize_t)(RFFHSTART1+mpi_rank*RFFHCOUNT1);
   block[0]  = RFFHBLOCK0;
   block[1]  = RFFHBLOCK1;
   stride[0] = RFFHSTRIDE0;
@@ -761,7 +761,7 @@ coll_read_test(void)
    *
    */
   start[0]  = RFSHSTART0;
-  start[1]  = RFSHSTART1+RFSHCOUNT1*mpi_rank;
+  start[1]  = (hsize_t)(RFSHSTART1+RFSHCOUNT1*mpi_rank);
   block[0]  = RFSHBLOCK0;
   block[1]  = RFSHBLOCK1;
   stride[0] = RFSHSTRIDE0;
@@ -791,7 +791,7 @@ coll_read_test(void)
    */
 
   start[0]  = RMFHSTART0;
-  start[1]  = RMFHSTART1+mpi_rank*RMFHCOUNT1;
+  start[1]  = (hsize_t)(RMFHSTART1+mpi_rank*RMFHCOUNT1);
   block[0]  = RMFHBLOCK0;
   block[1]  = RMFHBLOCK1;
   stride[0] = RMFHSTRIDE0;
@@ -813,7 +813,7 @@ coll_read_test(void)
    *
    */
   start[0]  = RMSHSTART0;
-  start[1]  = RMSHSTART1+mpi_rank*RMSHCOUNT1;
+  start[1]  = (hsize_t)(RMSHSTART1+mpi_rank*RMSHCOUNT1);
   block[0]  = RMSHBLOCK0;
   block[1]  = RMSHBLOCK1;
   stride[0] = RMSHSTRIDE0;
@@ -828,8 +828,8 @@ coll_read_test(void)
    * Initialize data buffer.
    */
 
-  HDmemset(matrix_out,0,sizeof(int)*MSPACE_DIM1*MSPACE_DIM2*mpi_size);
-  HDmemset(matrix_out1,0,sizeof(int)*MSPACE_DIM1*MSPACE_DIM2*mpi_size);
+  HDmemset(matrix_out,0,sizeof(int)*(size_t)MSPACE_DIM1*(size_t)MSPACE_DIM2*(size_t)mpi_size);
+  HDmemset(matrix_out1,0,sizeof(int)*(size_t)MSPACE_DIM1*(size_t)MSPACE_DIM2*(size_t)mpi_size);
 
   /*
    * Read data back to the buffer matrix_out.
@@ -1004,9 +1004,9 @@ lower_dim_size_comp_test__select_checker_board(
      * pre-C99 compilers again.
      */
 
-    base_count = dims[sel_offset] / (checker_edge_size * 2);
+    base_count = dims[sel_offset] / (hsize_t)(checker_edge_size * 2);
 
-    if ( (dims[sel_rank] % (checker_edge_size * 2)) > 0 ) {
+    if ( (dims[sel_rank] % (hsize_t)(checker_edge_size * 2)) > 0 ) {
 
         base_count++;
     }