Convert some H5MM calls to standard C equivalents (#2382)

* H5MM_calloc and malloc are now mapped to stdlib C calls
* H5MM_memcpy now maps directly to memcpy in release builds
* H5MM_memcpy is still implemented as a separate function that
   checks for buffer overlap when H5MM_DEBUG is defined
   (default w/ debug builds)
* Switches many library memcpy calls to use H5MM_memcpy
* Fixes a possible zero allocation in H5Olayout.c

23 files changed, 142 insertions, 174 deletions

diff --git a/config/cmake/HDFCompilerFlags.cmake b/config/cmake/HDFCompilerFlags.cmake
index 1878b9b..1dca910 100644
--- a/config/cmake/HDFCompilerFlags.cmake
+++ b/config/cmake/HDFCompilerFlags.cmake
@@ -310,6 +310,7 @@ if (HDF5_ENABLE_DEBUG_APIS)
       H5F_DEBUG
       H5HL_DEBUG
       H5I_DEBUG
+      H5MM_DEBUG
       H5O_DEBUG
       H5S_DEBUG
       H5T_DEBUG
diff --git a/configure.ac b/configure.ac
index c0eb47c..fadd1c1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2492,8 +2492,8 @@ AC_SUBST([INTERNAL_DEBUG_OUTPUT])
 ## too specialized or have huge performance hits. These
 ## are not listed in the "all" packages list.
 ##
-## all_packages="AC,B,B2,D,F,FA,FL,FS,HL,I,O,S,T,Z"
-all_packages="AC,B2,CX,D,F,HL,I,O,S,T,Z"
+## all_packages="AC,B,B2,D,F,FA,FL,FS,HL,I,MM,O,S,T,Z"
+all_packages="AC,B2,CX,D,F,HL,I,MM,O,S,T,Z"
 
 case "X-$INTERNAL_DEBUG_OUTPUT" in
   X-yes|X-all)
diff --git a/src/H5CS.c b/src/H5CS.c
index d8ee8d7..203c281 100644
--- a/src/H5CS.c
+++ b/src/H5CS.c
@@ -248,7 +248,7 @@ H5CS_copy_stack(void)
 
     /* Copy pointers on old stack to new one */
     /* (Strings don't need to be duplicated, they are statically allocated) */
-    memcpy(new_stack->rec, old_stack->rec, sizeof(char *) * old_stack->nused);
+    H5MM_memcpy(new_stack->rec, old_stack->rec, sizeof(char *) * old_stack->nused);
     new_stack->nused = new_stack->nalloc = old_stack->nused;
 
     /* Set the return value */
diff --git a/src/H5Dchunk.c b/src/H5Dchunk.c
index 8f34c2f..956baf3 100644
--- a/src/H5Dchunk.c
+++ b/src/H5Dchunk.c
@@ -2790,7 +2790,7 @@ H5D__chunk_read(H5D_io_info_t *io_info, H5D_dset_io_info_t *dset_info)
 
         /* Set up contiguous I/O info object */
         H5MM_memcpy(&ctg_io_info, io_info, sizeof(ctg_io_info));
-        memcpy(&ctg_dset_info, dset_info, sizeof(ctg_dset_info));
+        H5MM_memcpy(&ctg_dset_info, dset_info, sizeof(ctg_dset_info));
         ctg_dset_info.store      = &ctg_store;
         ctg_dset_info.layout_ops = *H5D_LOPS_CONTIG;
         ctg_io_info.dsets_info   = &ctg_dset_info;
@@ -2802,7 +2802,7 @@ H5D__chunk_read(H5D_io_info_t *io_info, H5D_dset_io_info_t *dset_info)
 
         /* Set up compact I/O info object */
         H5MM_memcpy(&cpt_io_info, io_info, sizeof(cpt_io_info));
-        memcpy(&cpt_dset_info, dset_info, sizeof(cpt_dset_info));
+        H5MM_memcpy(&cpt_dset_info, dset_info, sizeof(cpt_dset_info));
         cpt_dset_info.store      = &cpt_store;
         cpt_dset_info.layout_ops = *H5D_LOPS_COMPACT;
         cpt_io_info.dsets_info   = &cpt_dset_info;
@@ -2950,7 +2950,7 @@ H5D__chunk_write(H5D_io_info_t *io_info, H5D_dset_io_info_t *dset_info)
 
     /* Set up contiguous I/O info object */
     H5MM_memcpy(&ctg_io_info, io_info, sizeof(ctg_io_info));
-    memcpy(&ctg_dset_info, dset_info, sizeof(ctg_dset_info));
+    H5MM_memcpy(&ctg_dset_info, dset_info, sizeof(ctg_dset_info));
     ctg_dset_info.store      = &ctg_store;
     ctg_dset_info.layout_ops = *H5D_LOPS_CONTIG;
     ctg_io_info.dsets_info   = &ctg_dset_info;
@@ -2962,7 +2962,7 @@ H5D__chunk_write(H5D_io_info_t *io_info, H5D_dset_io_info_t *dset_info)
 
     /* Set up compact I/O info object */
     H5MM_memcpy(&cpt_io_info, io_info, sizeof(cpt_io_info));
-    memcpy(&cpt_dset_info, dset_info, sizeof(cpt_dset_info));
+    H5MM_memcpy(&cpt_dset_info, dset_info, sizeof(cpt_dset_info));
     cpt_dset_info.store      = &cpt_store;
     cpt_dset_info.layout_ops = *H5D_LOPS_COMPACT;
     cpt_io_info.dsets_info   = &cpt_dset_info;
diff --git a/src/H5Dmpio.c b/src/H5Dmpio.c
index 82bcf02..2c4c29e 100644
--- a/src/H5Dmpio.c
+++ b/src/H5Dmpio.c
@@ -3772,7 +3772,7 @@ H5D__mpio_share_chunk_modification_data(H5D_filtered_collective_io_info_t *chunk
             mod_data_p = msg_send_bufs[num_send_requests];
 
             /* Store the chunk's index into the buffer */
-            memcpy(mod_data_p, &chunk_entry->index_info.chunk_idx, sizeof(hsize_t));
+            H5MM_memcpy(mod_data_p, &chunk_entry->index_info.chunk_idx, sizeof(hsize_t));
             mod_data_p += sizeof(hsize_t);
 
             /* Serialize the chunk's file dataspace into the buffer */
@@ -4491,7 +4491,7 @@ H5D__mpio_collective_filtered_chunk_update(H5D_filtered_collective_io_info_t *ch
 
         if (msg_ptr) {
             /* Retrieve the chunk's index value */
-            memcpy(&chunk_idx, msg_ptr, sizeof(hsize_t));
+            H5MM_memcpy(&chunk_idx, msg_ptr, sizeof(hsize_t));
             msg_ptr += sizeof(hsize_t);
 
             /* Find the chunk entry according to its chunk index */
diff --git a/src/H5Dscatgath.c b/src/H5Dscatgath.c
index 4516f1f..a9158bf 100644
--- a/src/H5Dscatgath.c
+++ b/src/H5Dscatgath.c
@@ -118,7 +118,7 @@ H5D__scatter_file(const H5D_io_info_t *_io_info, const H5D_dset_io_info_t *_dset
 
     /* Set up temporary I/O info object */
     H5MM_memcpy(&tmp_io_info, _io_info, sizeof(*_io_info));
-    memcpy(&tmp_dset_info, _dset_info, sizeof(*_dset_info));
+    H5MM_memcpy(&tmp_dset_info, _dset_info, sizeof(*_dset_info));
     tmp_io_info.op_type    = H5D_IO_OP_WRITE;
     tmp_dset_info.buf.cvp  = _buf;
     tmp_io_info.dsets_info = &tmp_dset_info;
@@ -219,7 +219,7 @@ H5D__gather_file(const H5D_io_info_t *_io_info, const H5D_dset_io_info_t *_dset_
 
     /* Set up temporary I/O info object */
     H5MM_memcpy(&tmp_io_info, _io_info, sizeof(*_io_info));
-    memcpy(&tmp_dset_info, _dset_info, sizeof(*_dset_info));
+    H5MM_memcpy(&tmp_dset_info, _dset_info, sizeof(*_dset_info));
     tmp_io_info.op_type    = H5D_IO_OP_READ;
     tmp_dset_info.buf.vp   = _buf;
     tmp_io_info.dsets_info = &tmp_dset_info;
diff --git a/src/H5FDonion.c b/src/H5FDonion.c
index dcec221..a9d11e0 100644
--- a/src/H5FDonion.c
+++ b/src/H5FDonion.c
@@ -295,7 +295,7 @@ H5Pget_fapl_onion(hid_t fapl_id, H5FD_onion_fapl_info_t *fa_out)
     if (NULL == (info_ptr = (const H5FD_onion_fapl_info_t *)H5P_peek_driver_info(plist)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "bad VFL driver info");
 
-    memcpy(fa_out, info_ptr, sizeof(H5FD_onion_fapl_info_t));
+    H5MM_memcpy(fa_out, info_ptr, sizeof(H5FD_onion_fapl_info_t));
 
 done:
     FUNC_LEAVE_API(ret_value)
@@ -514,7 +514,7 @@ H5FD__onion_commit_new_revision_record(H5FD_onion_t *file)
 
         if (NULL == (new_list = H5MM_calloc((history->n_revisions + 1) * sizeof(H5FD_onion_record_loc_t))))
             HGOTO_ERROR(H5E_VFL, H5E_CANTALLOC, FAIL, "unable to resize record pointer list");
-        memcpy(new_list, history->record_locs, sizeof(H5FD_onion_record_loc_t) * history->n_revisions);
+        H5MM_memcpy(new_list, history->record_locs, sizeof(H5FD_onion_record_loc_t) * history->n_revisions);
         H5MM_xfree(history->record_locs);
         history->record_locs                                   = new_list;
         new_list                                               = NULL;
@@ -980,7 +980,7 @@ H5FD__onion_open(const char *filename, unsigned flags, hid_t fapl_id, haddr_t ma
 
     /* Initialize file structure fields */
 
-    memcpy(&(file->fa), fa, sizeof(H5FD_onion_fapl_info_t));
+    H5MM_memcpy(&(file->fa), fa, sizeof(H5FD_onion_fapl_info_t));
 
     file->header.version   = H5FD_ONION_HEADER_VERSION_CURR;
     file->header.page_size = file->fa.page_size; /* guarded on FAPL-set */
@@ -1523,7 +1523,7 @@ H5FD__onion_write(H5FD_t *_file, H5FD_mem_t type, hid_t H5_ATTR_UNUSED dxpl_id,
                 if (H5FD_read(file->onion_file, H5FD_MEM_DRAW, entry_out->phys_addr, page_size, page_buf) < 0)
                     HGOTO_ERROR(H5E_VFL, H5E_READERROR, FAIL, "can't get working file data");
                 /* Overlay delta from input buffer onto page buffer. */
-                memcpy(page_buf + page_gap_head, buf, page_n_used);
+                H5MM_memcpy(page_buf + page_gap_head, buf, page_n_used);
                 write_buf = page_buf;
             } /* end if partial page */
 
@@ -1571,7 +1571,7 @@ H5FD__onion_write(H5FD_t *_file, H5FD_mem_t type, hid_t H5_ATTR_UNUSED dxpl_id,
 
             /* Copy input buffer to temporary page buffer */
             assert((page_size - page_gap_head) >= page_n_used);
-            memcpy(page_buf + page_gap_head, buf, page_n_used);
+            H5MM_memcpy(page_buf + page_gap_head, buf, page_n_used);
             write_buf = page_buf;
 
         } /* end if data range does not span entire page */
diff --git a/src/H5FDonion_header.c b/src/H5FDonion_header.c
index a346ecf..55a632c 100644
--- a/src/H5FDonion_header.c
+++ b/src/H5FDonion_header.c
@@ -142,34 +142,34 @@ H5FD__onion_header_decode(unsigned char *buf, H5FD_onion_header_t *header)
 
     ptr  = buf + 5;
     ui32 = 0;
-    memcpy(&ui32, ptr, 3);
+    H5MM_memcpy(&ui32, ptr, 3);
     ui8p = (uint8_t *)&ui32;
     UINT32DECODE(ui8p, header->flags);
     ptr += 3;
 
-    memcpy(&ui32, ptr, 4);
+    H5MM_memcpy(&ui32, ptr, 4);
     ui8p = (uint8_t *)&ui32;
     UINT32DECODE(ui8p, header->page_size);
     ptr += 4;
 
-    memcpy(&ui64, ptr, 8);
+    H5MM_memcpy(&ui64, ptr, 8);
     ui8p = (uint8_t *)&ui64;
     UINT32DECODE(ui8p, header->origin_eof);
     ptr += 8;
 
-    memcpy(&ui64, ptr, 8);
+    H5MM_memcpy(&ui64, ptr, 8);
     ui8p = (uint8_t *)&ui64;
     UINT32DECODE(ui8p, header->history_addr);
     ptr += 8;
 
-    memcpy(&ui64, ptr, 8);
+    H5MM_memcpy(&ui64, ptr, 8);
     ui8p = (uint8_t *)&ui64;
     UINT32DECODE(ui8p, header->history_size);
     ptr += 8;
 
     sum = H5_checksum_fletcher32(buf, (size_t)(ptr - buf));
 
-    memcpy(&ui32, ptr, 4);
+    H5MM_memcpy(&ui32, ptr, 4);
     ui8p = (uint8_t *)&ui32;
     UINT32DECODE(ui8p, header->checksum);
     ptr += 4;
@@ -214,9 +214,9 @@ H5FD__onion_header_encode(H5FD_onion_header_t *header, unsigned char *buf, uint3
     assert(H5FD_ONION_HEADER_VERSION_CURR == header->version);
     assert(0 == (header->flags & 0xFF000000)); /* max three bits long */
 
-    memcpy(ptr, H5FD_ONION_HEADER_SIGNATURE, 4);
+    H5MM_memcpy(ptr, H5FD_ONION_HEADER_SIGNATURE, 4);
     ptr += 4;
-    memcpy(ptr, (unsigned char *)&header->version, 1);
+    H5MM_memcpy(ptr, (unsigned char *)&header->version, 1);
     ptr += 1;
     UINT32ENCODE(ptr, header->flags);
     ptr -= 1; /* truncate to three bytes */
diff --git a/src/H5FDonion_history.c b/src/H5FDonion_history.c
index e559e80..875d638 100644
--- a/src/H5FDonion_history.c
+++ b/src/H5FDonion_history.c
@@ -180,7 +180,7 @@ H5FD__onion_history_decode(unsigned char *buf, H5FD_onion_history_t *history)
 
     ptr = buf + 8;
 
-    memcpy(&ui64, ptr, 8);
+    H5MM_memcpy(&ui64, ptr, 8);
     ui8p = (uint8_t *)&ui64;
     UINT64DECODE(ui8p, n_revisions);
     ptr += 8;
@@ -207,19 +207,19 @@ H5FD__onion_history_decode(unsigned char *buf, H5FD_onion_history_t *history)
             uint64_t record_size;
             uint64_t phys_addr;
 
-            memcpy(&ui64, ptr, 8);
+            H5MM_memcpy(&ui64, ptr, 8);
             ui8p = (uint8_t *)&ui64;
             UINT64DECODE(ui8p, phys_addr);
             H5_CHECKED_ASSIGN(rloc->phys_addr, haddr_t, phys_addr, uint64_t);
             ptr += 8;
 
-            memcpy(&ui64, ptr, 8);
+            H5MM_memcpy(&ui64, ptr, 8);
             ui8p = (uint8_t *)&ui64;
             UINT64DECODE(ui8p, record_size);
             H5_CHECKED_ASSIGN(rloc->record_size, hsize_t, record_size, uint64_t);
             ptr += 8;
 
-            memcpy(&ui32, ptr, 4);
+            H5MM_memcpy(&ui32, ptr, 4);
             ui8p = (uint8_t *)&ui32;
             UINT32DECODE(ui8p, rloc->checksum);
             ptr += 4;
@@ -228,7 +228,7 @@ H5FD__onion_history_decode(unsigned char *buf, H5FD_onion_history_t *history)
 
     sum = H5_checksum_fletcher32(buf, (size_t)(ptr - buf));
 
-    memcpy(&ui32, ptr, 4);
+    H5MM_memcpy(&ui32, ptr, 4);
     ui8p = (uint8_t *)&ui32;
     UINT32DECODE(ui8p, history->checksum);
     ptr += 4;
@@ -275,7 +275,7 @@ H5FD__onion_history_encode(H5FD_onion_history_t *history, unsigned char *buf, ui
     assert(buf != NULL);
     assert(checksum != NULL);
 
-    memcpy(ptr, H5FD_ONION_HISTORY_SIGNATURE, 4);
+    H5MM_memcpy(ptr, H5FD_ONION_HISTORY_SIGNATURE, 4);
     ptr += 4;
     UINT32ENCODE(ptr, vers_u32);
     UINT64ENCODE(ptr, history->n_revisions);
diff --git a/src/H5FDonion_index.c b/src/H5FDonion_index.c
index a6215ab..fae87ca 100644
--- a/src/H5FDonion_index.c
+++ b/src/H5FDonion_index.c
@@ -483,7 +483,7 @@ H5FD__onion_revision_index_insert(H5FD_onion_revision_index_t *rix, const H5FD_o
                 if (entry->phys_addr != node->entry_data.phys_addr) {
                     HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "physical address mismatch");
                 }
-                memcpy(&node->entry_data, entry, sizeof(H5FD_onion_index_entry_t));
+                H5MM_memcpy(&node->entry_data, entry, sizeof(H5FD_onion_index_entry_t));
                 append_dest = NULL; /* Node updated, do not append */
                 break;
             }
@@ -496,7 +496,7 @@ H5FD__onion_revision_index_insert(H5FD_onion_revision_index_t *rix, const H5FD_o
             HGOTO_ERROR(H5E_VFL, H5E_CANTALLOC, FAIL, "cannot allocate new ash chain node");
         node->version = H5FD_ONION_REVISION_INDEX_HASH_CHAIN_NODE_VERSION_CURR;
         node->next    = NULL;
-        memcpy(&node->entry_data, entry, sizeof(H5FD_onion_index_entry_t));
+        H5MM_memcpy(&node->entry_data, entry, sizeof(H5FD_onion_index_entry_t));
         *append_dest = node;
         rix->n_entries++;
     }
@@ -612,25 +612,25 @@ H5FD__onion_revision_record_decode(unsigned char *buf, H5FD_onion_revision_recor
 
     ptr = buf + 8;
 
-    memcpy(&ui64, ptr, 8);
+    H5MM_memcpy(&ui64, ptr, 8);
     ui8p = (uint8_t *)&ui64;
     UINT64DECODE(ui8p, record->revision_num);
     ptr += 8;
 
-    memcpy(&ui64, ptr, 8);
+    H5MM_memcpy(&ui64, ptr, 8);
     ui8p = (uint8_t *)&ui64;
     UINT64DECODE(ui8p, record->parent_revision_num);
     ptr += 8;
 
-    memcpy(record->time_of_creation, ptr, 16);
+    H5MM_memcpy(record->time_of_creation, ptr, 16);
     ptr += 16;
 
-    memcpy(&ui64, ptr, 8);
+    H5MM_memcpy(&ui64, ptr, 8);
     ui8p = (uint8_t *)&ui64;
     UINT64DECODE(ui8p, record->logical_eof);
     ptr += 8;
 
-    memcpy(&ui32, ptr, 4);
+    H5MM_memcpy(&ui32, ptr, 4);
     ui8p = (uint8_t *)&ui32;
     UINT32DECODE(ui8p, page_size);
     ptr += 4;
@@ -645,12 +645,12 @@ H5FD__onion_revision_record_decode(unsigned char *buf, H5FD_onion_revision_recor
          record->archival_index.page_size_log2++)
         ;
 
-    memcpy(&ui64, ptr, 8);
+    H5MM_memcpy(&ui64, ptr, 8);
     ui8p = (uint8_t *)&ui64;
     UINT64DECODE(ui8p, n_entries);
     ptr += 8;
 
-    memcpy(&ui32, ptr, 4);
+    H5MM_memcpy(&ui32, ptr, 4);
     ui8p = (uint8_t *)&ui32;
     UINT32DECODE(ui8p, comment_size);
     ptr += 4;
@@ -671,7 +671,7 @@ H5FD__onion_revision_record_decode(unsigned char *buf, H5FD_onion_revision_recor
         for (size_t i = 0; i < n_entries; i++) {
             entry = &record->archival_index.list[i];
 
-            memcpy(&ui64, ptr, 8);
+            H5MM_memcpy(&ui64, ptr, 8);
             ui8p = (uint8_t *)&ui64;
             UINT64DECODE(ui8p, entry->logical_page);
             ptr += 8;
@@ -682,12 +682,12 @@ H5FD__onion_revision_record_decode(unsigned char *buf, H5FD_onion_revision_recor
 
             entry->logical_page = entry->logical_page >> record->archival_index.page_size_log2;
 
-            memcpy(&ui64, ptr, 8);
+            H5MM_memcpy(&ui64, ptr, 8);
             ui8p = (uint8_t *)&ui64;
             UINT64DECODE(ui8p, entry->phys_addr);
             ptr += 8;
 
-            memcpy(&ui32, ptr, 4);
+            H5MM_memcpy(&ui32, ptr, 4);
             ui8p = (uint8_t *)&ui32;
             UINT32DECODE(ui8p, sum);
             ptr += 4;
@@ -706,13 +706,13 @@ H5FD__onion_revision_record_decode(unsigned char *buf, H5FD_onion_revision_recor
     else {
         if (record->comment == NULL)
             HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, 0, "no comment pointer");
-        memcpy(record->comment, ptr, comment_size);
+        H5MM_memcpy(record->comment, ptr, comment_size);
     }
     ptr += comment_size;
 
     sum = H5_checksum_fletcher32(buf, (size_t)(ptr - buf));
 
-    memcpy(&ui32, ptr, 4);
+    H5MM_memcpy(&ui32, ptr, 4);
     ui8p = (uint8_t *)&ui32;
     UINT32DECODE(ui8p, record->checksum);
     ptr += 4;
@@ -765,12 +765,12 @@ H5FD__onion_revision_record_encode(H5FD_onion_revision_record_t *record, unsigne
 
     page_size = (uint32_t)(1 << record->archival_index.page_size_log2);
 
-    memcpy(ptr, H5FD_ONION_REVISION_RECORD_SIGNATURE, 4);
+    H5MM_memcpy(ptr, H5FD_ONION_REVISION_RECORD_SIGNATURE, 4);
     ptr += 4;
     UINT32ENCODE(ptr, vers_u32);
     UINT64ENCODE(ptr, record->revision_num);
     UINT64ENCODE(ptr, record->parent_revision_num);
-    memcpy(ptr, record->time_of_creation, 16);
+    H5MM_memcpy(ptr, record->time_of_creation, 16);
     ptr += 16;
     UINT64ENCODE(ptr, record->logical_eof);
     UINT32ENCODE(ptr, page_size);
@@ -798,7 +798,7 @@ H5FD__onion_revision_record_encode(H5FD_onion_revision_record_t *record, unsigne
 
     if (record->comment_size > 0) {
         assert(record->comment != NULL && *record->comment != '\0');
-        memcpy(ptr, record->comment, record->comment_size);
+        H5MM_memcpy(ptr, record->comment, record->comment_size);
         ptr += record->comment_size;
     }
 
@@ -876,7 +876,8 @@ H5FD__onion_merge_revision_index_into_archival_index(const H5FD_onion_revision_i
         const H5FD_onion_revision_index_hash_chain_node_t *node = NULL;
 
         for (node = rix->_hash_table[i]; node != NULL; node = node->next) {
-            memcpy(&new_aix.list[new_aix.n_entries], &node->entry_data, sizeof(H5FD_onion_index_entry_t));
+            H5MM_memcpy(&new_aix.list[new_aix.n_entries], &node->entry_data,
+                        sizeof(H5FD_onion_index_entry_t));
             new_aix.n_entries++;
         }
     }
@@ -901,7 +902,7 @@ H5FD__onion_merge_revision_index_into_archival_index(const H5FD_onion_revision_i
 
         /* Add only if page not already added from revision index */
         if (H5FD__onion_archival_index_find(&new_aix, aix->list[i].logical_page, &entry) == 0) {
-            memcpy(&kept_list[n_kept], &aix->list[i], sizeof(H5FD_onion_index_entry_t));
+            H5MM_memcpy(&kept_list[n_kept], &aix->list[i], sizeof(H5FD_onion_index_entry_t));
             n_kept++;
         }
     }
@@ -914,12 +915,12 @@ H5FD__onion_merge_revision_index_into_archival_index(const H5FD_onion_revision_i
         HGOTO_ERROR(H5E_VFL, H5E_CANTALLOC, FAIL, "unable to allocate exact-size archival index list");
 
     /* Copy (new) revision list entries to replacement list */
-    memcpy(aix->list, new_aix.list, sizeof(H5FD_onion_index_entry_t) * new_aix.n_entries);
+    H5MM_memcpy(aix->list, new_aix.list, sizeof(H5FD_onion_index_entry_t) * new_aix.n_entries);
     aix->n_entries = new_aix.n_entries;
 
     /* Copy (old) kept archival list entries to replacement list */
     if (n_kept > 0) {
-        memcpy(&aix->list[aix->n_entries], kept_list, sizeof(H5FD_onion_index_entry_t) * n_kept);
+        H5MM_memcpy(&aix->list[aix->n_entries], kept_list, sizeof(H5FD_onion_index_entry_t) * n_kept);
         aix->n_entries += n_kept;
     }
 
diff --git a/src/H5FDros3.c b/src/H5FDros3.c
index c6414af..19de079 100644
--- a/src/H5FDros3.c
+++ b/src/H5FDros3.c
@@ -809,13 +809,13 @@ H5Pset_fapl_ros3_token(hid_t fapl_id, const char *token)
         if (H5P_get(plist, ROS3_TOKEN_PROP_NAME, &token_src) < 0)
             HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "unable to get token value");
 
-        memcpy(token_src, token, HDstrlen(token) + 1);
+        H5MM_memcpy(token_src, token, HDstrlen(token) + 1);
     }
     else {
         token_src = (char *)malloc(sizeof(char) * (H5FD_ROS3_MAX_SECRET_TOK_LEN + 1));
         if (token_src == NULL)
             HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "cannot make space for token_src variable.");
-        memcpy(token_src, token, HDstrlen(token) + 1);
+        H5MM_memcpy(token_src, token, HDstrlen(token) + 1);
         if (H5P_insert(plist, ROS3_TOKEN_PROP_NAME, sizeof(char *), &token_src, NULL, NULL, NULL, NULL,
                        H5FD__ros3_str_token_delete, H5FD__ros3_str_token_copy, H5FD__ros3_str_token_cmp,
                        H5FD__ros3_str_token_close) < 0)
diff --git a/src/H5FDsubfiling/H5FDioc.c b/src/H5FDsubfiling/H5FDioc.c
index 81ad0e7..570c747 100644
--- a/src/H5FDsubfiling/H5FDioc.c
+++ b/src/H5FDsubfiling/H5FDioc.c
@@ -399,7 +399,7 @@ H5Pget_fapl_ioc(hid_t fapl_id, H5FD_ioc_config_t *config_out)
     }
     else {
         /* Copy the IOC fapl data out */
-        memcpy(config_out, config_ptr, sizeof(H5FD_ioc_config_t));
+        H5MM_memcpy(config_out, config_ptr, sizeof(H5FD_ioc_config_t));
     }
 
 done:
@@ -666,7 +666,7 @@ H5FD__ioc_fapl_copy(const void *_old_fa)
     if (NULL == new_fa_ptr)
         H5_SUBFILING_GOTO_ERROR(H5E_VFL, H5E_CANTALLOC, NULL, "unable to allocate log file FAPL");
 
-    memcpy(new_fa_ptr, old_fa_ptr, sizeof(H5FD_ioc_config_t));
+    H5MM_memcpy(new_fa_ptr, old_fa_ptr, sizeof(H5FD_ioc_config_t));
 
     ret_value = (void *)new_fa_ptr;
 
@@ -790,7 +790,7 @@ H5FD__ioc_open(const char *name, unsigned flags, hid_t fapl_id, haddr_t maxaddr)
     }
 
     /* Fill in the file config values */
-    memcpy(&file_ptr->fa, config_ptr, sizeof(H5FD_ioc_config_t));
+    H5MM_memcpy(&file_ptr->fa, config_ptr, sizeof(H5FD_ioc_config_t));
 
     /* Fully resolve the given filepath and get its dirname */
     if (H5_resolve_pathname(name, file_ptr->comm, &file_ptr->file_path) < 0)
diff --git a/src/H5FDsubfiling/H5FDioc_threads.c b/src/H5FDsubfiling/H5FDioc_threads.c
index f4da503..cb3458e 100644
--- a/src/H5FDsubfiling/H5FDioc_threads.c
+++ b/src/H5FDsubfiling/H5FDioc_threads.c
@@ -1304,7 +1304,7 @@ ioc_io_queue_add_entry(ioc_data_t *ioc_data, sf_work_request_t *wk_req_ptr)
     assert(entry_ptr);
     assert(entry_ptr->magic == H5FD_IOC__IO_Q_ENTRY_MAGIC);
 
-    memcpy((void *)(&(entry_ptr->wk_req)), (const void *)wk_req_ptr, sizeof(sf_work_request_t));
+    H5MM_memcpy((void *)(&(entry_ptr->wk_req)), (const void *)wk_req_ptr, sizeof(sf_work_request_t));
 
     /* must obtain io_queue mutex before appending */
     hg_thread_mutex_lock(&ioc_data->io_queue.q_mutex);
diff --git a/src/H5FDsubfiling/H5FDsubfiling.c b/src/H5FDsubfiling/H5FDsubfiling.c
index 6a04f68..89afa01 100644
--- a/src/H5FDsubfiling/H5FDsubfiling.c
+++ b/src/H5FDsubfiling/H5FDsubfiling.c
@@ -553,7 +553,7 @@ H5Pget_fapl_subfiling(hid_t fapl_id, H5FD_subfiling_config_t *config_out)
     }
     else {
         /* Copy the subfiling fapl data out */
-        memcpy(config_out, config_ptr, sizeof(H5FD_subfiling_config_t));
+        H5MM_memcpy(config_out, config_ptr, sizeof(H5FD_subfiling_config_t));
 
         /* Copy the driver info value */
         if (H5FD__copy_plist(config_ptr->ioc_fapl_id, &(config_out->ioc_fapl_id)) < 0)
@@ -811,7 +811,7 @@ H5FD__subfiling_sb_encode(H5FD_t *_file, char *name, unsigned char *buf)
 
     /* Encode config file prefix string */
     if (sf_context->config_file_prefix) {
-        memcpy(p, sf_context->config_file_prefix, prefix_len);
+        H5MM_memcpy(p, sf_context->config_file_prefix, prefix_len);
         p += prefix_len;
     }
 
@@ -826,7 +826,7 @@ H5FD__subfiling_sb_encode(H5FD_t *_file, char *name, unsigned char *buf)
                                     "unable to encode IOC VFD's superblock information");
 
         /* Copy the IOC VFD's name into our buffer */
-        memcpy(p, ioc_name, 9);
+        H5MM_memcpy(p, ioc_name, 9);
     }
 
 done:
@@ -893,9 +893,9 @@ H5FD__subfiling_sb_decode(H5FD_t *_file, const char *name, const unsigned char *
                 H5_SUBFILING_GOTO_ERROR(H5E_RESOURCE, H5E_CANTALLOC, FAIL,
                                         "can't allocate space for config file prefix string");
 
-            memcpy(sf_context->config_file_prefix, p, tmpu64);
+            H5MM_memcpy(sf_context->config_file_prefix, p, tmpu64);
 
-            /* Just in case.. */
+            /* Just in case... */
             sf_context->config_file_prefix[tmpu64 - 1] = '\0';
         }
 
@@ -905,7 +905,7 @@ H5FD__subfiling_sb_decode(H5FD_t *_file, const char *name, const unsigned char *
     if (file->sf_file) {
         char ioc_name[9];
 
-        memcpy(ioc_name, p, 9);
+        H5MM_memcpy(ioc_name, p, 9);
         p += 9;
 
         if (H5FD_sb_load(file->sf_file, ioc_name, p) < 0)
@@ -960,7 +960,7 @@ H5FD__subfiling_fapl_get(H5FD_t *_file)
     }
 
     /* Copy the fields of the structure */
-    memcpy(fa, &(file->fa), sizeof(H5FD_subfiling_config_t));
+    H5MM_memcpy(fa, &(file->fa), sizeof(H5FD_subfiling_config_t));
 
     /* Copy the driver info value */
     if (H5FD__copy_plist(file->fa.ioc_fapl_id, &(fa->ioc_fapl_id)) < 0)
@@ -1036,7 +1036,7 @@ H5FD__subfiling_fapl_copy(const void *_old_fa)
         H5_SUBFILING_GOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed");
     }
 
-    memcpy(new_fa, old_fa, sizeof(H5FD_subfiling_config_t));
+    H5MM_memcpy(new_fa, old_fa, sizeof(H5FD_subfiling_config_t));
 
     if (H5FD__copy_plist(old_fa->ioc_fapl_id, &(new_fa->ioc_fapl_id)) < 0)
         H5_SUBFILING_GOTO_ERROR(H5E_VFL, H5E_BADVALUE, NULL, "can't copy the IOC FAPL");
@@ -1169,7 +1169,7 @@ H5FD__subfiling_open(const char *name, unsigned flags, hid_t fapl_id, haddr_t ma
         config_ptr = &default_config;
     }
 
-    memcpy(&file_ptr->fa, config_ptr, sizeof(H5FD_subfiling_config_t));
+    H5MM_memcpy(&file_ptr->fa, config_ptr, sizeof(H5FD_subfiling_config_t));
     if (H5FD__copy_plist(config_ptr->ioc_fapl_id, &(file_ptr->fa.ioc_fapl_id)) < 0) {
         file_ptr->fa.ioc_fapl_id = H5I_INVALID_HID;
         H5_SUBFILING_GOTO_ERROR(H5E_VFL, H5E_BADVALUE, NULL, "can't copy FAPL");
diff --git a/src/H5FL.c b/src/H5FL.c
index ec952b7..5ed6430 100644
--- a/src/H5FL.c
+++ b/src/H5FL.c
@@ -957,7 +957,7 @@ H5FL_blk_free(H5FL_blk_head_t *head, void *block)
         unsigned char *block_ptr = ((unsigned char *)block) - sizeof(H5FL_track_t);
         H5FL_track_t   trk;
 
-        memcpy(&trk, block_ptr, sizeof(H5FL_track_t));
+        H5MM_memcpy(&trk, block_ptr, sizeof(H5FL_track_t));
 
         /* Free tracking information about the allocation location */
         H5CS_close_stack(trk.stack);
@@ -979,7 +979,7 @@ H5FL_blk_free(H5FL_blk_head_t *head, void *block)
                 trk.next->prev = trk.prev;
         } /* end else */
 
-        memcpy(block_ptr, &trk, sizeof(H5FL_track_t));
+        H5MM_memcpy(block_ptr, &trk, sizeof(H5FL_track_t));
     }
 #endif /* H5FL_TRACK */
 
@@ -1079,7 +1079,7 @@ H5FL_blk_realloc(H5FL_blk_head_t *head, void *block, size_t new_size H5FL_TRACK_
                 unsigned char *block_ptr = ((unsigned char *)block) - sizeof(H5FL_track_t);
                 H5FL_track_t   trk;
 
-                memcpy(&trk, block_ptr, sizeof(H5FL_track_t));
+                H5MM_memcpy(&trk, block_ptr, sizeof(H5FL_track_t));
 
                 /* Release previous tracking information */
                 H5CS_close_stack(trk.stack);
@@ -1099,7 +1099,7 @@ H5FL_blk_realloc(H5FL_blk_head_t *head, void *block, size_t new_size H5FL_TRACK_
                 trk.func = call_func;
                 trk.line = call_line;
 
-                memcpy(block_ptr, &trk, sizeof(H5FL_track_t));
+                H5MM_memcpy(block_ptr, &trk, sizeof(H5FL_track_t));
             }
 #endif /* H5FL_TRACK */
             ret_value = block;
@@ -1380,7 +1380,7 @@ H5FL_arr_free(H5FL_arr_head_t *head, void *obj)
         unsigned char *block_ptr = ((unsigned char *)obj) - sizeof(H5FL_track_t);
         H5FL_track_t   trk;
 
-        memcpy(&trk, block_ptr, sizeof(H5FL_track_t));
+        H5MM_memcpy(&trk, block_ptr, sizeof(H5FL_track_t));
 
         /* Free tracking information about the allocation location */
         H5CS_close_stack(trk.stack);
@@ -1402,7 +1402,7 @@ H5FL_arr_free(H5FL_arr_head_t *head, void *obj)
                 trk.next->prev = trk.prev;
         } /* end else */
 
-        memcpy(block_ptr, &trk, sizeof(H5FL_track_t));
+        H5MM_memcpy(block_ptr, &trk, sizeof(H5FL_track_t));
     }
 #endif
 
@@ -1631,7 +1631,7 @@ H5FL_arr_realloc(H5FL_arr_head_t *head, void *obj, size_t new_elem H5FL_TRACK_PA
             unsigned char *block_ptr = ((unsigned char *)obj) - sizeof(H5FL_track_t);
             H5FL_track_t   trk;
 
-            memcpy(&trk, block_ptr, sizeof(H5FL_track_t));
+            H5MM_memcpy(&trk, block_ptr, sizeof(H5FL_track_t));
 
             /* Release previous tracking information */
             H5CS_close_stack(trk.stack);
@@ -1651,7 +1651,7 @@ H5FL_arr_realloc(H5FL_arr_head_t *head, void *obj, size_t new_elem H5FL_TRACK_PA
             trk.func = call_func;
             trk.line = call_line;
 
-            memcpy(block_ptr, &trk, sizeof(H5FL_track_t));
+            H5MM_memcpy(block_ptr, &trk, sizeof(H5FL_track_t));
 #endif
             ret_value = obj;
         }
diff --git a/src/H5MM.c b/src/H5MM.c
index 609f946..d48ec80 100644
--- a/src/H5MM.c
+++ b/src/H5MM.c
@@ -55,63 +55,6 @@
 /*******************/
 
 /*-------------------------------------------------------------------------
- * Function:    H5MM_malloc
- *
- * Purpose:     Similar to the C89 version of malloc().
- *
- *              On size of 0, we return a NULL pointer instead of the
- *              standard-allowed 'special' pointer since that's more
- *              difficult to check as a return value. This is still
- *              considered an error condition since allocations of zero
- *              bytes usually indicate problems.
- *
- * Return:      Success:    Pointer to new memory
- *              Failure:    NULL
- *-------------------------------------------------------------------------
- */
-void *
-H5MM_malloc(size_t size)
-{
-    void *ret_value = NULL;
-
-    /* Use FUNC_ENTER_NOAPI_NOINIT_NOERR here to avoid performance issues */
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
-
-    ret_value = malloc(size);
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5MM_malloc() */
-
-/*-------------------------------------------------------------------------
- * Function:    H5MM_calloc
- *
- * Purpose:     Similar to the C89 version of calloc(), except this
- *              routine just takes a 'size' parameter.
- *
- *              On size of 0, we return a NULL pointer instead of the
- *              standard-allowed 'special' pointer since that's more
- *              difficult to check as a return value. This is still
- *              considered an error condition since allocations of zero
- *              bytes usually indicate problems.
- *
- * Return:      Success:    Pointer to new memory
- *              Failure:    NULL
- *-------------------------------------------------------------------------
- */
-void *
-H5MM_calloc(size_t size)
-{
-    void *ret_value = NULL;
-
-    /* Use FUNC_ENTER_NOAPI_NOINIT_NOERR here to avoid performance issues */
-    FUNC_ENTER_NOAPI_NOINIT_NOERR
-
-    ret_value = calloc(1, size);
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5MM_calloc() */
-
-/*-------------------------------------------------------------------------
  * Function:    H5MM_realloc
  *
  * Purpose:     Similar semantics as C89's realloc(). Specifically, the
@@ -283,6 +226,8 @@ H5MM_xfree_const(const void *mem)
     FUNC_LEAVE_NOAPI(NULL)
 } /* end H5MM_xfree_const() */
 
+#ifdef H5MM_DEBUG
+
 /*-------------------------------------------------------------------------
  * Function:    H5MM_memcpy
  *
@@ -313,3 +258,5 @@ H5MM_memcpy(void *dest, const void *src, size_t n)
     FUNC_LEAVE_NOAPI(ret)
 
 } /* end H5MM_memcpy() */
+
+#endif /* H5MM_DEBUG */
diff --git a/src/H5MMprivate.h b/src/H5MMprivate.h
index f94a433..39bba2c 100644
--- a/src/H5MMprivate.h
+++ b/src/H5MMprivate.h
@@ -14,7 +14,7 @@
  *
  * Created:             H5MMprivate.h
  *
- * Purpose:             Private header for memory management.
+ * Purpose:             Private header for memory management
  *
  *-------------------------------------------------------------------------
  */
@@ -26,19 +26,33 @@
 /* Private headers needed by this file */
 #include "H5private.h"
 
-#define H5MM_free(Z) free(Z)
+/* Uncomment this macro to enable some extra memory checks
+ *
+ * This can also be defined at configure time, which we do in debug builds
+ * by default.
+ */
+/* #define H5MM_DEBUG */
+
+#define H5MM_calloc(Z) calloc(1, Z)
+#define H5MM_free(Z)   free(Z)
+#define H5MM_malloc(Z) malloc(Z)
+
+#ifndef H5MM_DEBUG
+#define H5MM_memcpy(D, S, N) memcpy(D, S, N)
+#endif /* !H5MM_DEBUG */
 
 /*
  * Library prototypes...
  */
-H5_DLL void *H5MM_malloc(size_t size) H5_ATTR_MALLOC;
-H5_DLL void *H5MM_calloc(size_t size) H5_ATTR_MALLOC;
 H5_DLL void *H5MM_realloc(void *mem, size_t size);
 H5_DLL char *H5MM_xstrdup(const char *s) H5_ATTR_MALLOC;
 H5_DLL char *H5MM_strdup(const char *s) H5_ATTR_MALLOC;
 H5_DLL char *H5MM_strndup(const char *s, size_t n) H5_ATTR_MALLOC;
 H5_DLL void *H5MM_xfree(void *mem);
 H5_DLL void *H5MM_xfree_const(const void *mem);
+
+#ifdef H5MM_DEBUG
 H5_DLL void *H5MM_memcpy(void *dest, const void *src, size_t n);
+#endif
 
 #endif /* H5MMprivate_H */
diff --git a/src/H5Olayout.c b/src/H5Olayout.c
index 4ee2f82..f725b5c 100644
--- a/src/H5Olayout.c
+++ b/src/H5Olayout.c
@@ -582,9 +582,15 @@ H5O__layout_decode(H5F_t *f, H5O_t H5_ATTR_UNUSED *open_oh, unsigned H5_ATTR_UNU
                     H5F_DECODE_LENGTH(f, heap_block_p, tmp_hsize);
 
                     /* Allocate entry list */
-                    if (NULL == (mesg->storage.u.virt.list = (H5O_storage_virtual_ent_t *)H5MM_calloc(
-                                     (size_t)tmp_hsize * sizeof(H5O_storage_virtual_ent_t))))
-                        HGOTO_ERROR(H5E_OHDR, H5E_CANTALLOC, NULL, "unable to allocate heap block");
+                    if (tmp_hsize > 0) {
+                        if (NULL == (mesg->storage.u.virt.list = (H5O_storage_virtual_ent_t *)H5MM_calloc(
+                                         (size_t)tmp_hsize * sizeof(H5O_storage_virtual_ent_t))))
+                            HGOTO_ERROR(H5E_OHDR, H5E_CANTALLOC, NULL, "unable to allocate heap block");
+                    }
+                    else {
+                        /* Avoid zero-size allocation */
+                        mesg->storage.u.virt.list = NULL;
+                    }
                     mesg->storage.u.virt.list_nalloc = (size_t)tmp_hsize;
                     mesg->storage.u.virt.list_nused  = (size_t)tmp_hsize;
 
diff --git a/src/H5RS.c b/src/H5RS.c
index 0bf40b1..1ad22f3 100644
--- a/src/H5RS.c
+++ b/src/H5RS.c
@@ -124,7 +124,7 @@ H5RS__xstrdup(H5RS_str_t *rs, const char *s)
         if (NULL == (rs->s = (char *)H5FL_BLK_MALLOC(str_buf, rs->max)))
             HGOTO_ERROR(H5E_RS, H5E_CANTALLOC, FAIL, "memory allocation failed");
         if (len)
-            memcpy(rs->s, s, len);
+            H5MM_memcpy(rs->s, s, len);
         rs->end  = rs->s + len;
         *rs->end = '\0';
         rs->len  = len;
@@ -430,7 +430,7 @@ H5RS_acat(H5RS_str_t *rs, const char *s)
                 HGOTO_ERROR(H5E_RS, H5E_CANTRESIZE, FAIL, "can't resize ref-counted string buffer");
 
         /* Append the string */
-        memcpy(rs->end, s, len);
+        H5MM_memcpy(rs->end, s, len);
         rs->end += len;
         *rs->end = '\0';
         rs->len += len;
@@ -479,7 +479,7 @@ H5RS_ancat(H5RS_str_t *rs, const char *s, size_t n)
                 HGOTO_ERROR(H5E_RS, H5E_CANTRESIZE, FAIL, "can't resize ref-counted string buffer");
 
         /* Append the string */
-        memcpy(rs->end, s, n);
+        H5MM_memcpy(rs->end, s, n);
         rs->end += n;
         *rs->end = '\0';
         rs->len += n;
diff --git a/src/H5Tinit_float.c b/src/H5Tinit_float.c
index efab5b6..3a8c0bd 100644
--- a/src/H5Tinit_float.c
+++ b/src/H5Tinit_float.c
@@ -79,11 +79,11 @@
          * and interfere with detection of the various properties below unless we                            \
          * know to ignore them. */                                                                           \
         _v1 = (TYPE)4.0L;                                                                                    \
-        memcpy(_buf1, (const void *)&_v1, sizeof(TYPE));                                                     \
+        H5MM_memcpy(_buf1, (const void *)&_v1, sizeof(TYPE));                                                \
         for (_i = 0; _i < (int)sizeof(TYPE); _i++)                                                           \
             for (_byte_mask = (unsigned char)1; _byte_mask; _byte_mask = (unsigned char)(_byte_mask << 1)) { \
                 _buf1[_i] ^= _byte_mask;                                                                     \
-                memcpy((void *)&_v2, (const void *)_buf1, sizeof(TYPE));                                     \
+                H5MM_memcpy((void *)&_v2, (const void *)_buf1, sizeof(TYPE));                                \
                 H5_GCC_CLANG_DIAG_OFF("float-equal")                                                         \
                 if (_v1 != _v2)                                                                              \
                     _pad_mask[_i] |= _byte_mask;                                                             \
@@ -96,8 +96,8 @@
             _v3 = _v1;                                                                                       \
             _v1 += _v2;                                                                                      \
             _v2 /= (TYPE)256.0L;                                                                             \
-            memcpy(_buf1, (const void *)&_v1, sizeof(TYPE));                                                 \
-            memcpy(_buf3, (const void *)&_v3, sizeof(TYPE));                                                 \
+            H5MM_memcpy(_buf1, (const void *)&_v1, sizeof(TYPE));                                            \
+            H5MM_memcpy(_buf3, (const void *)&_v3, sizeof(TYPE));                                            \
             _j = H5T__byte_cmp(sizeof(TYPE), _buf3, _buf1, _pad_mask);                                       \
             if (_j >= 0) {                                                                                   \
                 INFO.perm[_i] = _j;                                                                          \
diff --git a/src/H5Tref.c b/src/H5Tref.c
index ddc73ac..0e6d6dd 100644
--- a/src/H5Tref.c
+++ b/src/H5Tref.c
@@ -737,7 +737,7 @@ H5T__ref_mem_write(H5VL_object_t *src_file, const void *src_buf, size_t src_size
     } /* end if */
 
     /* Set output info */
-    memcpy(dst_ref, &tmp_ref, sizeof(tmp_ref));
+    H5MM_memcpy(dst_ref, &tmp_ref, sizeof(tmp_ref));
 
 done:
     if ((file_id != H5I_INVALID_HID) && (H5I_dec_ref(file_id) < 0))
diff --git a/src/H5Tvlen.c b/src/H5Tvlen.c
index 87f0600..ac5d3c0 100644
--- a/src/H5Tvlen.c
+++ b/src/H5Tvlen.c
@@ -360,14 +360,11 @@ H5T__vlen_mem_seq_getlen(H5VL_object_t H5_ATTR_UNUSED *file, const void *_vl, si
 
     FUNC_ENTER_PACKAGE_NOERR
 
-    /* Check parameter */
     assert(_vl);
     assert(len);
 
-    /* Copy to ensure correct alignment.  memcpy is best here because
-     * it optimizes to fast code.
-     */
-    memcpy(&vl, _vl, sizeof(hvl_t));
+    /* Copy to ensure correct alignment */
+    H5MM_memcpy(&vl, _vl, sizeof(hvl_t));
 
     *len = vl.len;
 
@@ -390,10 +387,10 @@ H5T__vlen_mem_seq_getptr(void *_vl)
 
     FUNC_ENTER_PACKAGE_NOERR
 
-    /* check parameters, return result */
     assert(_vl);
-    /* Copy to ensure correct alignment. */
-    memcpy(&vl, _vl, sizeof(hvl_t));
+
+    /* Copy to ensure correct alignment */
+    H5MM_memcpy(&vl, _vl, sizeof(hvl_t));
 
     FUNC_LEAVE_NOAPI(vl.p)
 } /* end H5T__vlen_mem_seq_getptr() */
@@ -414,11 +411,10 @@ H5T__vlen_mem_seq_isnull(const H5VL_object_t H5_ATTR_UNUSED *file, void *_vl, hb
 
     FUNC_ENTER_PACKAGE_NOERR
 
-    /* Check parameters */
     assert(_vl);
 
-    /* Copy to ensure correct alignment. */
-    memcpy(&vl, _vl, sizeof(hvl_t));
+    /* Copy to ensure correct alignment */
+    H5MM_memcpy(&vl, _vl, sizeof(hvl_t));
 
     *isnull = ((vl.len == 0 || vl.p == NULL) ? TRUE : FALSE);
 
@@ -470,11 +466,11 @@ H5T__vlen_mem_seq_read(H5VL_object_t H5_ATTR_UNUSED *file, void *_vl, void *buf,
 
     FUNC_ENTER_PACKAGE_NOERR
 
-    /* check parameters, copy data */
     assert(buf);
     assert(_vl);
-    /* Copy to ensure correct alignment. */
-    memcpy(&vl, _vl, sizeof(hvl_t));
+
+    /* Copy to ensure correct alignment */
+    H5MM_memcpy(&vl, _vl, sizeof(hvl_t));
     assert(vl.p);
 
     H5MM_memcpy(buf, vl.p, len);
@@ -549,11 +545,10 @@ H5T__vlen_mem_str_getlen(H5VL_object_t H5_ATTR_UNUSED *file, const void *_vl, si
 
     FUNC_ENTER_PACKAGE_NOERR
 
-    /* check parameters */
     assert(_vl);
 
-    /* Copy to ensure correct alignment. */
-    memcpy(&s, _vl, sizeof(char *));
+    /* Copy to ensure correct alignment */
+    H5MM_memcpy(&s, _vl, sizeof(char *));
 
     *len = HDstrlen(s);
 
@@ -576,10 +571,10 @@ H5T__vlen_mem_str_getptr(void *_vl)
 
     FUNC_ENTER_PACKAGE_NOERR
 
-    /* check parameters */
     assert(_vl);
-    /* Copy to ensure correct alignment. */
-    memcpy(&s, _vl, sizeof(char *));
+
+    /* Copy to ensure correct alignment */
+    H5MM_memcpy(&s, _vl, sizeof(char *));
 
     FUNC_LEAVE_NOAPI(s)
 } /* end H5T__vlen_mem_str_getptr() */
@@ -600,8 +595,8 @@ H5T__vlen_mem_str_isnull(const H5VL_object_t H5_ATTR_UNUSED *file, void *_vl, hb
 
     FUNC_ENTER_PACKAGE_NOERR
 
-    /* Copy to ensure correct alignment. */
-    memcpy(&s, _vl, sizeof(char *));
+    /* Copy to ensure correct alignment */
+    H5MM_memcpy(&s, _vl, sizeof(char *));
 
     *isnull = (s == NULL ? TRUE : FALSE);
 
@@ -647,14 +642,13 @@ H5T__vlen_mem_str_read(H5VL_object_t H5_ATTR_UNUSED *file, void *_vl, void *buf,
     FUNC_ENTER_PACKAGE_NOERR
 
     if (len > 0) {
-        /* check parameters */
         assert(buf);
         assert(_vl);
-        /* Copy to ensure correct alignment. */
-        memcpy(&s, _vl, sizeof(char *));
 
+        /* Copy to ensure correct alignment */
+        H5MM_memcpy(&s, _vl, sizeof(char *));
         H5MM_memcpy(buf, s, len);
-    } /* end if */
+    }
 
     FUNC_LEAVE_NOAPI(SUCCEED)
 } /* end H5T__vlen_mem_str_read() */
diff --git a/src/H5encode.h b/src/H5encode.h
index a9172ff..5be75d5 100644
--- a/src/H5encode.h
+++ b/src/H5encode.h
@@ -17,6 +17,11 @@
 #ifndef H5encode_H
 #define H5encode_H
 
+/***********/
+/* Headers */
+/***********/
+#include "H5MMprivate.h" /* Memory management                        */
+
 /**************************/
 /* Library Private Macros */
 /**************************/
@@ -128,7 +133,7 @@
                                                                                                              \
         HDcompile_assert(sizeof(double) == 8);                                                               \
         HDcompile_assert(sizeof(double) == sizeof(uint64_t));                                                \
-        memcpy(&_n, &n, sizeof(double));                                                                     \
+        H5MM_memcpy(&_n, &n, sizeof(double));                                                                \
         for (_u = 0; _u < sizeof(uint64_t); _u++, _n >>= 8)                                                  \
             *_p++ = (uint8_t)(_n & 0xff);                                                                    \
         (p) = (uint8_t *)(p) + 8;                                                                            \
@@ -245,7 +250,7 @@
         (p) += 8;                                                                                            \
         for (_u = 0; _u < sizeof(uint64_t); _u++)                                                            \
             _n = (_n << 8) | *(--p);                                                                         \
-        memcpy(&(n), &_n, sizeof(double));                                                                   \
+        H5MM_memcpy(&(n), &_n, sizeof(double));                                                              \
         (p) += 8;                                                                                            \
     } while (0)