HDFFV-10980 - h5diff uses new ref APIs

47 files changed, 1454 insertions, 467 deletions

diff --git a/tools/lib/CMakeLists.txt b/tools/lib/CMakeLists.txt
index f46eb23..2acfab0 100644
--- a/tools/lib/CMakeLists.txt
+++ b/tools/lib/CMakeLists.txt
@@ -39,6 +39,7 @@ if (NOT ONLY_SHARED_LIBS)
       INTERFACE "$<INSTALL_INTERFACE:$<INSTALL_PREFIX>/include>"
   )
   #target_compile_definitions(${HDF5_TOOLS_LIB_TARGET} PRIVATE H5_TOOLS_DEBUG)
+  #target_compile_definitions(${HDF5_TOOLS_LIB_TARGET} PRIVATE H5DIFF_DEBUG)
   TARGET_C_PROPERTIES (${HDF5_TOOLS_LIB_TARGET} STATIC)
   target_link_libraries (${HDF5_TOOLS_LIB_TARGET}
       PUBLIC ${HDF5_LIB_TARGET}
@@ -59,6 +60,7 @@ if (BUILD_SHARED_LIBS)
   target_compile_definitions(${HDF5_TOOLS_LIBSH_TARGET}
       PUBLIC "H5_BUILT_AS_DYNAMIC_LIB"
       #PRIVATE H5_TOOLS_DEBUG
+      #PRIVATE H5DIFF_DEBUG
   )
   TARGET_C_PROPERTIES (${HDF5_TOOLS_LIBSH_TARGET} SHARED)
   target_link_libraries (${HDF5_TOOLS_LIBSH_TARGET}
diff --git a/tools/lib/h5diff.c b/tools/lib/h5diff.c
index b22af18..74bc2f9 100644
--- a/tools/lib/h5diff.c
+++ b/tools/lib/h5diff.c
@@ -262,6 +262,7 @@ static void
 build_match_list (const char *objname1, trav_info_t *info1, const char *objname2, trav_info_t *info2,
         trav_table_t ** table_out, diff_opt_t *opts)
 {
+    H5TOOLS_ERR_INIT(int, 0)
     size_t   curr1 = 0;
     size_t   curr2 = 0;
     unsigned infile[2];
@@ -274,9 +275,9 @@ build_match_list (const char *objname1, trav_info_t *info1, const char *objname2
     int      cmp;
     trav_table_t *table = NULL;
     size_t   idx;
-    int      ret_value = 0;
 
-    h5difftrace("build_match_list start\n");
+    H5TOOLS_PUSH_STACK();
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "build_match_list start - errstat:%d", opts->err_stat);
     /* init */
     trav_table_init(&table);
     if (table == NULL) {
@@ -372,7 +373,11 @@ build_match_list (const char *objname1, trav_info_t *info1, const char *objname2
 
 done:
     *table_out = table;
-    h5difftrace("build_match_list finish\n");
+
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
+
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "build_match_list finish");
 }
 
 
@@ -399,7 +404,7 @@ trav_grp_objs(const char *path, const H5O_info_t *oinfo,
 static herr_t
 trav_grp_symlinks(const char *path, const H5L_info_t *linfo, void *udata)
 {
-    herr_t         ret_value = 0;
+    H5TOOLS_ERR_INIT(herr_t, 0)
     trav_info_t   *tinfo = (trav_info_t *)udata;
     diff_opt_t    *opts = (diff_opt_t *)tinfo->opts;
     h5tool_link_info_t lnk_info;
@@ -409,6 +414,7 @@ trav_grp_symlinks(const char *path, const H5L_info_t *linfo, void *udata)
     /* init linkinfo struct */
     HDmemset(&lnk_info, 0, sizeof(h5tool_link_info_t));
 
+    H5TOOLS_PUSH_STACK();
     if (!opts->follow_links) {
         trav_info_visit_lnk(path, linfo, tinfo);
         HGOTO_DONE(0);
@@ -489,6 +495,8 @@ trav_grp_symlinks(const char *path, const H5L_info_t *linfo, void *udata)
 done:
     if (lnk_info.trg_path)
         HDfree(lnk_info.trg_path);
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return ret_value;
 }
 
@@ -509,7 +517,7 @@ h5diff(const char *fname1,
                const char *objname2,
                diff_opt_t *opts)
 {
-    int           ret_value = 0;
+    H5TOOLS_ERR_INIT(int, 0)
     hid_t         file1_id = -1;
     hid_t         file2_id = -1;
     char          filenames[2][MAX_FILENAME];
@@ -541,7 +549,8 @@ h5diff(const char *fname1,
     /* list for common objects */
     trav_table_t *match_list = NULL;
 
-    h5difftrace("h5diff start\n");
+    H5TOOLS_PUSH_STACK();
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "h5diff start");
     /* init filenames */
     HDmemset(filenames, 0, MAX_FILENAME * 2);
     /* init link info struct */
@@ -566,13 +575,14 @@ h5diff(const char *fname1,
         parallel_print("h5diff: <%s>: unable to open file\n", fname1);
         H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "<%s>: unable to open file\n", fname1);
     } /* end if */
-
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "file1_id = %s", fname1);
 
     /* open file 2 */
     if((file2_id = h5tools_fopen(fname2, H5F_ACC_RDONLY, H5P_DEFAULT, NULL, NULL, (size_t)0)) < 0) {
         parallel_print("h5diff: <%s>: unable to open file\n", fname2);
         H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "<%s>: unable to open file\n", fname2);
     } /* end if */
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "file2_id = %s", fname2);
 
     /*-------------------------------------------------------------------------
     * Initialize the info structs
@@ -581,7 +591,7 @@ h5diff(const char *fname1,
     trav_info_init(fname1, file1_id, &info1_obj);
     trav_info_init(fname2, file2_id, &info2_obj);
 
-    h5difftrace("trav_info_init initialized\n");
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "trav_info_init initialized");
     /* if any object is specified */
     if (objname1) {
         /* make the given object1 fullpath, start with "/"  */
@@ -622,7 +632,7 @@ h5diff(const char *fname1,
         /*----------------------------------------------------------
          * check if obj1 is root, group, single object or symlink
          */
-        h5difftrace("h5diff check if obj1 is root, group, single object or symlink\n");
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "h5diff check if obj1=%s is root, group, single object or symlink", obj1fullname);
         if(!HDstrcmp(obj1fullname, "/")) {
             obj1type = H5TRAV_TYPE_GROUP;
         }
@@ -672,7 +682,7 @@ h5diff(const char *fname1,
         /*----------------------------------------------------------
          * check if obj2 is root, group, single object or symlink
          */
-        h5difftrace("h5diff check if obj2 is root, group, single object or symlink\n");
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "h5diff check if obj2=%s is root, group, single object or symlink", obj2fullname);
         if(!HDstrcmp(obj2fullname, "/")) {
             obj2type = H5TRAV_TYPE_GROUP;
         }
@@ -721,7 +731,7 @@ h5diff(const char *fname1,
     }
     /* if no object specified */
     else {
-        h5difftrace("h5diff no object specified\n");
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "h5diff no object specified");
         /* set root group */
         obj1fullname = (char*)HDstrdup("/");
         obj1type = H5TRAV_TYPE_GROUP;
@@ -729,7 +739,7 @@ h5diff(const char *fname1,
         obj2type = H5TRAV_TYPE_GROUP;
     }
 
-    h5diffdebug2("get any symbolic links info - errstat:%d\n", opts->err_stat);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "get any symbolic links info - errstat:%d", opts->err_stat);
     /* get any symbolic links info */
     l_ret1 = H5tools_get_symlink_info(file1_id, obj1fullname, &trg_linfo1, opts->follow_links);
     l_ret2 = H5tools_get_symlink_info(file2_id, obj2fullname, &trg_linfo2, opts->follow_links);
@@ -745,10 +755,10 @@ h5diff(const char *fname1,
         /*-------------------------------
          * check symbolic link (object1)
          */
-        h5difftrace("h5diff check symbolic link (object1)\n");
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "h5diff check symbolic link (object1)");
         /* dangling link */
         if (l_ret1 == 0) {
-            h5difftrace("h5diff ... dangling link\n");
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "h5diff ... dangling link");
             if (opts->no_dangle_links) {
                 /* treat dangling link as error */
                 if(opts->m_verbose)
@@ -771,25 +781,25 @@ h5diff(const char *fname1,
         }
         else if(l_ret1 != 2) { /* symbolic link */
             obj1type = (h5trav_type_t)trg_linfo1.trg_type;
-            h5difftrace("h5diff ... ... trg_linfo1.trg_type == H5L_TYPE_HARD\n");
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "h5diff ... ... trg_linfo1.trg_type == H5L_TYPE_HARD");
             if (info1_lp != NULL) {
                 size_t idx = info1_lp->nused - 1;
 
-                h5difftrace("h5diff ... ... ... info1_obj not null\n");
+                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "h5diff ... ... ... info1_obj not null");
                 info1_lp->paths[idx].type = (h5trav_type_t)trg_linfo1.trg_type;
                 info1_lp->paths[idx].objno = trg_linfo1.objno;
                 info1_lp->paths[idx].fileno = trg_linfo1.fileno;
             }
-            h5difftrace("h5diff check symbolic link (object1) finished\n");
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "h5diff check symbolic link (object1) finished");
         }
 
         /*-------------------------------
          * check symbolic link (object2)
          */
-        h5difftrace("h5diff check symbolic link (object2)\n");
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "h5diff check symbolic link (object2)");
         /* dangling link */
         if (l_ret2 == 0) {
-            h5difftrace("h5diff ... dangling link\n");
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "h5diff ... dangling link");
             if (opts->no_dangle_links) {
                 /* treat dangling link as error */
                 if(opts->m_verbose)
@@ -815,12 +825,12 @@ h5diff(const char *fname1,
             if (info2_lp != NULL) {
                 size_t idx = info2_lp->nused - 1;
 
-                h5difftrace("h5diff ... ... ... info2_obj not null\n");
+                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "h5diff ... ... ... info2_obj not null");
                 info2_lp->paths[idx].type = (h5trav_type_t)trg_linfo2.trg_type;
                 info2_lp->paths[idx].objno = trg_linfo2.objno;
                 info2_lp->paths[idx].fileno = trg_linfo2.fileno;
             }
-            h5difftrace("h5diff check symbolic link (object1) finished\n");
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "h5diff check symbolic link (object1) finished");
         }
     } /* end of if follow symlinks */
 
@@ -832,7 +842,7 @@ h5diff(const char *fname1,
     */
 
     if(!(opts->m_verbose || opts->m_report)) {
-        h5difftrace("h5diff NOT (opts->m_verbose || opts->m_report)\n");
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "h5diff NOT (opts->m_verbose || opts->m_report)");
         /* if no danglink links */
         if (l_ret1 > 0 && l_ret2 > 0)
             if (h5tools_is_obj_same(file1_id, obj1fullname, file2_id, obj2fullname) != 0)
@@ -841,7 +851,7 @@ h5diff(const char *fname1,
 
     both_objs_grp = (obj1type == H5TRAV_TYPE_GROUP && obj2type == H5TRAV_TYPE_GROUP);
     if (both_objs_grp) {
-        h5difftrace("h5diff both_objs_grp TRUE\n");
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "h5diff both_objs_grp TRUE");
         /*
          * traverse group1
          */
@@ -870,7 +880,7 @@ h5diff(const char *fname1,
        } /* end if */
         info2_lp = info2_grp;
     }
-    h5diffdebug2("groups traversed - errstat:%d\n", opts->err_stat);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "groups traversed - errstat:%d", opts->err_stat);
 
 #ifdef H5_HAVE_PARALLEL
     if(g_Parallel) {
@@ -890,8 +900,10 @@ h5diff(const char *fname1,
     } /* end if */
 #endif
 
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "build_match_list next - errstat:%d", opts->err_stat);
     /* process the objects */
     build_match_list (obj1fullname, info1_lp, obj2fullname, info2_lp, &match_list, opts);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "build_match_list finished - errstat:%d", opts->err_stat);
     if (both_objs_grp) {
         /*------------------------------------------------------
          * print the list
@@ -915,6 +927,7 @@ h5diff(const char *fname1,
              parallel_print ("\n");
          } /* end if */
     }
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_match next - errstat:%d", opts->err_stat);
     nfound = diff_match(file1_id, obj1fullname, info1_lp,
                         file2_id, obj2fullname, info2_lp,
                         match_list, opts);
@@ -957,8 +970,10 @@ done:
         H5Fclose(file2_id);
     } H5E_END_TRY;
 
-    h5difftrace("h5diff finish\n");
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "h5diff finish - errstat:%d", opts->err_stat);
 
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return nfound;
 }
 
@@ -985,9 +1000,9 @@ diff_match(hid_t file1_id, const char *grp1, trav_info_t *info1,
                    hid_t file2_id, const char *grp2, trav_info_t *info2,
                    trav_table_t *table, diff_opt_t *opts)
 {
+    H5TOOLS_ERR_INIT(int, opts->err_stat)
     hsize_t      nfound = 0;
     unsigned     i;
-    int          ret_value = opts->err_stat;
     const char  *grp1_path = "";
     const char  *grp2_path = "";
     char        *obj1_fullpath = NULL;
@@ -996,7 +1011,8 @@ diff_match(hid_t file1_id, const char *grp1, trav_info_t *info1,
     size_t       idx1 = 0;
     size_t       idx2 = 0;
 
-    h5difftrace("diff_match start\n");
+    H5TOOLS_PUSH_STACK();
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_match start - errstat:%d", opts->err_stat);
     /*
      * if not root, prepare object name to be pre-appended to group path to
      * make full path
@@ -1049,7 +1065,7 @@ diff_match(hid_t file1_id, const char *grp1, trav_info_t *info1,
 #endif
 
     for(i = 0; i < table->nobjs; i++) {
-        h5diffdebug3("diff for common objects[%d] - errstat:%d\n", i, opts->err_stat);
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff for common objects[%d] - errstat:%d", i, opts->err_stat);
         if(table->objs[i].flags[0] && table->objs[i].flags[1]) {
             /* make full path for obj1 */
 #ifdef H5_HAVE_ASPRINTF
@@ -1066,7 +1082,7 @@ diff_match(hid_t file1_id, const char *grp1, trav_info_t *info1,
                 HDstrcat(obj1_fullpath, table->objs[i].name);
             }
 #endif /* H5_HAVE_ASPRINTF */
-            h5diffdebug2("diff_match path1 - %s\n", obj1_fullpath);
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_match path1 - %s", obj1_fullpath);
 
             /* make full path for obj2 */
 #ifdef H5_HAVE_ASPRINTF
@@ -1083,7 +1099,7 @@ diff_match(hid_t file1_id, const char *grp1, trav_info_t *info1,
                 HDstrcat(obj2_fullpath, table->objs[i].name);
             }
 #endif /* H5_HAVE_ASPRINTF */
-            h5diffdebug2("diff_match path2 - %s\n", obj2_fullpath);
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_match path2 - %s", obj2_fullpath);
 
             /* get index to figure out type of the object in file1 */
             while(info1->paths[idx1].path && (HDstrcmp(obj1_fullpath, info1->paths[idx1].path) != 0))
@@ -1099,6 +1115,7 @@ diff_match(hid_t file1_id, const char *grp1, trav_info_t *info1,
 
             opts->cmn_objs = 1;
             if(!g_Parallel) {
+                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff paths - errstat:%d", opts->err_stat);
                 nfound += diff(file1_id, obj1_fullpath,
                                file2_id, obj2_fullpath,
                             opts, &argdata);
@@ -1107,7 +1124,7 @@ diff_match(hid_t file1_id, const char *grp1, trav_info_t *info1,
             else {
                 int workerFound = 0;
 
-                h5difftrace("Beginning of big else block\n");
+                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "Beginning of big else block");
                 /* We're in parallel mode */
                 /* Since the data type of diff value is hsize_t which can
                 * be arbitary large such that there is no MPI type that
@@ -1261,7 +1278,7 @@ diff_match(hid_t file1_id, const char *grp1, trav_info_t *info1,
                 HDfree(obj2_fullpath);
         } /* end if */
     } /* end for */
-    h5diffdebug2("done with for loop - errstat:%d\n", opts->err_stat);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "done with for loop - errstat:%d", opts->err_stat);
 
 #ifdef H5_HAVE_PARALLEL
     if(g_Parallel) {
@@ -1338,7 +1355,7 @@ diff_match(hid_t file1_id, const char *grp1, trav_info_t *info1,
         /* Print any final data waiting in our queue */
         print_incoming_data();
     } /* end if */
-    h5difftrace("done with if block\n");
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "done with if block");
 
     HDfree(workerTasks);
     }
@@ -1349,8 +1366,11 @@ diff_match(hid_t file1_id, const char *grp1, trav_info_t *info1,
 /* free table */
     if (table)
         trav_table_free(table);
-    h5diffdebug2("diff_match finish:%d\n", nfound);
 
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_match finish diffs=%d - errstat:%d", nfound, opts->err_stat);
+
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return nfound;
 }
 
@@ -1376,14 +1396,14 @@ diff(hid_t file1_id,
               diff_opt_t * opts,
               diff_args_t *argdata)
 {
-    int           ret_value = opts->err_stat;
+    H5TOOLS_ERR_INIT(int, opts->err_stat)
     int           status = -1;
-    hid_t         dset1_id = -1;
-    hid_t         dset2_id = -1;
-    hid_t         type1_id = -1;
-    hid_t         type2_id = -1;
-    hid_t         grp1_id = -1;
-    hid_t         grp2_id = -1;
+    hid_t         dset1_id = H5I_INVALID_HID;
+    hid_t         dset2_id = H5I_INVALID_HID;
+    hid_t         type1_id = H5I_INVALID_HID;
+    hid_t         type2_id = H5I_INVALID_HID;
+    hid_t         grp1_id = H5I_INVALID_HID;
+    hid_t         grp2_id = H5I_INVALID_HID;
     hbool_t       is_dangle_link1 = FALSE;
     hbool_t       is_dangle_link2 = FALSE;
     hbool_t       is_hard_link = FALSE;
@@ -1394,7 +1414,8 @@ diff(hid_t file1_id,
     h5tool_link_info_t linkinfo1;
     h5tool_link_info_t linkinfo2;
 
-    h5difftrace("diff start\n");
+    H5TOOLS_PUSH_STACK();
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff start - errstat:%d", opts->err_stat);
 
     /*init link info struct */
     HDmemset(&linkinfo1, 0, sizeof(h5tool_link_info_t));
@@ -1414,6 +1435,7 @@ diff(hid_t file1_id,
          * check dangling links for path1 and path2
          */
 
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff links");
         /* target object1 - get type and name */
         if ((status = H5tools_get_symlink_info(file1_id, path1, &linkinfo1, opts->follow_links)) < 0)
             H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5tools_get_symlink_info failed");
@@ -1462,6 +1484,7 @@ diff(hid_t file1_id,
     }
     /* if objects are not the same type */
     if (argdata->type[0] != argdata->type[1]) {
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff objects are not the same");
         if (opts->m_verbose||opts->m_list_not_cmp) {
             parallel_print("Not comparable: <%s> is of type %s and <%s> is of type %s\n",
             path1, get_type(argdata->type[0]),
@@ -1485,7 +1508,7 @@ diff(hid_t file1_id,
      * Perform this to match the outputs as bypassing.
      */
      if (argdata->is_same_trgobj) {
-        h5difftrace("argdata->is_same_trgobj\n");
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "argdata->is_same_trgobj");
         is_hard_link = (object_type == H5TRAV_TYPE_DATASET ||
                         object_type == H5TRAV_TYPE_NAMED_DATATYPE ||
                         object_type == H5TRAV_TYPE_GROUP);
@@ -1533,6 +1556,7 @@ diff(hid_t file1_id,
         *----------------------------------------------------------------------
         */
         case H5TRAV_TYPE_DATASET:
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff object type H5TRAV_TYPE_DATASET - errstat:%d", opts->err_stat);
             if((dset1_id = H5Dopen2(file1_id, path1, H5P_DEFAULT)) < 0)
                 H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Dopen2 failed");
             if((dset2_id = H5Dopen2(file2_id, path2, H5P_DEFAULT)) < 0)
@@ -1540,6 +1564,7 @@ diff(hid_t file1_id,
             /* verbose (-v) and report (-r) mode */
             if(opts->m_verbose || opts->m_report) {
                 do_print_objname("dataset", path1, path2, opts);
+                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "call diff_dataset 1:%s  2:%s ", path1, path2);
                 nfound = diff_dataset(file1_id, file2_id, path1, path2, opts);
                 print_found(nfound);
             }
@@ -1556,7 +1581,7 @@ diff(hid_t file1_id,
                     print_found(nfound);
                 }
             }
-            h5diffdebug2("diff after dataset:%d\n", nfound);
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff after dataset:%d - errstat:%d", nfound, opts->err_stat);
 
             /*---------------------------------------------------------
              * compare attributes
@@ -1564,9 +1589,10 @@ diff(hid_t file1_id,
              * referenced object
              *---------------------------------------------------------
              */
-            if(path1)
+            if(path1) {
+                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "call diff_attr 1:%s  2:%s ", path1, path2);
                 nfound += diff_attr(dset1_id, dset2_id, path1, path2, opts);
-
+            }
 
             if(H5Dclose(dset1_id) < 0)
                 H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Dclose failed");
@@ -1579,6 +1605,7 @@ diff(hid_t file1_id,
         *----------------------------------------------------------------------
         */
         case H5TRAV_TYPE_NAMED_DATATYPE:
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "H5TRAV_TYPE_NAMED_DATATYPE 1:%s  2:%s ", path1, path2);
             if((type1_id = H5Topen2(file1_id, path1, H5P_DEFAULT)) < 0)
                 H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Topen2 failed");
             if((type2_id = H5Topen2(file2_id, path2, H5P_DEFAULT)) < 0)
@@ -1603,8 +1630,10 @@ diff(hid_t file1_id,
              * referenced object
              *-----------------------------------------------------------------
              */
-            if(path1)
+            if(path1) {
+                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "call diff_attr 1:%s  2:%s ", path1, path2);
                 nfound += diff_attr(type1_id, type2_id, path1, path2, opts);
+            }
 
             if(H5Tclose(type1_id) < 0)
                 H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tclose failed");
@@ -1617,6 +1646,7 @@ diff(hid_t file1_id,
         *----------------------------------------------------------------------
         */
         case H5TRAV_TYPE_GROUP:
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "H5TRAV_TYPE_GROUP 1:%s  2:%s ", path1, path2);
             if(print_objname(opts, nfound))
                 do_print_objname("group", path1, path2, opts);
 
@@ -1635,8 +1665,10 @@ diff(hid_t file1_id,
              * referenced object
              *-----------------------------------------------------------------
              */
-            if(path1)
+            if(path1) {
+                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "call diff_attr 1:%s  2:%s ", path1, path2);
                 nfound += diff_attr(grp1_id, grp2_id, path1, path2, opts);
+            }
 
             if(H5Gclose(grp1_id) < 0)
                 H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Gclose failed");
@@ -1651,6 +1683,7 @@ diff(hid_t file1_id,
         */
         case H5TRAV_TYPE_LINK:
             {
+                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "H5TRAV_TYPE_LINK 1:%s  2:%s ", path1, path2);
                 status = HDstrcmp(linkinfo1.trg_path, linkinfo2.trg_path);
 
                 /* if the target link name is not same then the links are "different" */
@@ -1672,6 +1705,7 @@ diff(hid_t file1_id,
         */
         case H5TRAV_TYPE_UDLINK:
             {
+                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "H5TRAV_TYPE_UDLINK 1:%s  2:%s ", path1, path2);
                 /* Only external links will have a query function registered */
                 if(linkinfo1.linfo.type == H5L_TYPE_EXTERNAL && linkinfo2.linfo.type == H5L_TYPE_EXTERNAL) {
                     /* If the buffers are the same size, compare them */
@@ -1772,8 +1806,10 @@ done:
         /* enable error reporting */
     } H5E_END_TRY;
 
-    h5diffdebug3("diff finish:%d - errstat:%d\n", nfound, opts->err_stat);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff finish:%d - errstat:%d", nfound, opts->err_stat);
 
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return nfound;
 }
 
diff --git a/tools/lib/h5diff.h b/tools/lib/h5diff.h
index 26bcd95..0931c1a 100644
--- a/tools/lib/h5diff.h
+++ b/tools/lib/h5diff.h
@@ -71,7 +71,7 @@ typedef struct {
     hsize_t  count;                 /* count value */
     hbool_t  follow_links;          /* follow symbolic links */
     int      no_dangle_links;       /* return error when find dangling link */
-    int      err_stat;              /* an error ocurred (1, error, 0, no error) */
+    int      err_stat;              /* an error ocurred (2, error, 1, differences, 0, no error) */
     int      cmn_objs;              /* do we have common objects */
     int      not_cmp;               /* are the objects comparable */
     int      contents;              /* equal contents */
@@ -165,6 +165,13 @@ int diff_can_type( hid_t       f_type1, /* file data type */
                    diff_opt_t  *opts,
                    int         is_compound);
 
+hsize_t diff_attr_data(hid_t attr1_id,
+                  hid_t attr2_id,
+                  const char *attr1_name,
+                  const char *attr2_name,
+                  const char *path1,
+                  const char *path2,
+                  diff_opt_t *opts);
 
 hsize_t diff_attr(hid_t loc1_id,
                   hid_t loc2_id,
diff --git a/tools/lib/h5diff_array.c b/tools/lib/h5diff_array.c
index c83b88d..637cfa8 100644
--- a/tools/lib/h5diff_array.c
+++ b/tools/lib/h5diff_array.c
@@ -17,6 +17,8 @@
 #include "h5diff.h"
 #include "ph5diff.h"
 
+#define ATTR_NAME_MAX 255
+
 /*-------------------------------------------------------------------------
  * printf formatting
  *-------------------------------------------------------------------------
@@ -273,6 +275,7 @@ hsize_t diff_array(
         hid_t container1_id,
         hid_t container2_id) /* dataset where the reference came from*/
 {
+    H5TOOLS_ERR_INIT(int, 0)
     hsize_t         nfound = 0; /* number of differences found */
     size_t          size; /* size of datum */
     unsigned char  *mem1 = (unsigned char*) _mem1;
@@ -285,7 +288,8 @@ hsize_t diff_array(
     mcomp_t         members;
     H5T_class_t     type_class;
 
-    h5diffdebug2("diff_array start - errstat:%d\n", opts->err_stat);
+    H5TOOLS_PUSH_STACK();
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_array start - errstat:%d", opts->err_stat);
     /* get the size. */
     size = H5Tget_size(m_type);
     type_class = H5Tget_class(m_type);
@@ -310,6 +314,7 @@ hsize_t diff_array(
             pos[j] = 0;
     }
 
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_array type_class:%d", type_class);
     switch (type_class) {
     case H5T_NO_CLASS:
     case H5T_TIME:
@@ -370,6 +375,7 @@ hsize_t diff_array(
     case H5T_REFERENCE:
         HDmemset(&members, 0, sizeof(mcomp_t));
         get_member_types(m_type, &members);
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "call diff_datum nelmts:%d - errstat:%d", nelmts, opts->err_stat);
         for (i = 0; i < nelmts; i++) {
             nfound += diff_datum(mem1 + i * size, mem2 + i * size, m_type, i, rank, dims, acc, pos, opts,
                     name1, name2, container1_id, container2_id, &ph, &members);
@@ -378,8 +384,10 @@ hsize_t diff_array(
         } /* i */
         close_member_types(&members);
     } /* switch */
-    h5diffdebug3("diff_array finish:%d - errstat:%d\n", nfound, opts->err_stat);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_array finish:%d - errstat:%d", nfound, opts->err_stat);
 
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit: %d", nfound);
+    H5TOOLS_POP_STACK();
     return nfound;
 }
 
@@ -433,6 +441,7 @@ static hsize_t diff_datum(
         int *ph,             /*print header */
         mcomp_t *members)    /*compound members */
 {
+    H5TOOLS_ERR_INIT(hsize_t, opts->err_stat)
     unsigned char  *mem1 = (unsigned char*) _mem1;
     unsigned char  *mem2 = (unsigned char*) _mem2;
     size_t          u;
@@ -447,11 +456,11 @@ static hsize_t diff_datum(
     hbool_t         iszero1;
     hbool_t         iszero2;
     hsize_t         nfound = 0;    /* differences found */
-    hsize_t         ret_value = opts->err_stat;
     double          per;
     hbool_t         both_zero;
 
-    h5difftrace("diff_datum start\n");
+    H5TOOLS_PUSH_STACK();
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum start - errstat:%d", opts->err_stat);
 
     type_size = H5Tget_size(m_type);
     type_class = H5Tget_class(m_type);
@@ -480,7 +489,7 @@ static hsize_t diff_datum(
      *-------------------------------------------------------------------------
      */
     case H5T_COMPOUND:
-        h5difftrace("diff_datum H5T_COMPOUND\n");
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum H5T_COMPOUND");
         {
             hid_t memb_type = -1;
             nmembs = members->n;
@@ -500,7 +509,7 @@ static hsize_t diff_datum(
      *-------------------------------------------------------------------------
      */
     case H5T_STRING:
-        h5difftrace("diff_datum H5T_STRING\n");
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum H5T_STRING");
         {
             char *s = NULL;
             char *sx = NULL;
@@ -514,7 +523,7 @@ static hsize_t diff_datum(
 
             /* if variable length string */
             if (H5Tis_variable_str(m_type)) {
-                h5difftrace("diff_datum H5T_STRING variable\n");
+                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum H5T_STRING variable");
                 /* Get pointer to first string */
                 s1 = *(char **)((void *)mem1);
                 if (s1)
@@ -530,7 +539,7 @@ static hsize_t diff_datum(
                     size2 = 0;
             }
             else if (H5T_STR_NULLTERM == pad) {
-                h5difftrace("diff_datum H5T_STRING null term\n");
+                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum H5T_STRING null term");
                 /* Get pointer to first string */
                 s1 = (char*) mem1;
                 if (s1)
@@ -567,10 +576,10 @@ static hsize_t diff_datum(
              *       of length of strings.
              *       For now mimic the previous way.
              */
-            h5diffdebug2("diff_datum string size:%d\n", size1);
-            h5diffdebug2("diff_datum string size:%d\n", size2);
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum string size:%d", size1);
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum string size:%d", size2);
             if (size1 != size2) {
-                h5difftrace("diff_datum string sizes\n");
+                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum string sizes difference");
                 nfound++;
             }
             if (size1 < size2) {
@@ -607,7 +616,7 @@ static hsize_t diff_datum(
      *-------------------------------------------------------------------------
      */
     case H5T_BITFIELD:
-        h5difftrace("diff_datum H5T_BITFIELD\n");
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum H5T_BITFIELD");
         /* byte-by-byte comparison */
         for (u = 0; u < type_size; u++)
             nfound += character_compare_opt(mem1 + u, mem2 + u, index, rank, dims, acc, pos, opts, obj1, obj2, ph);
@@ -618,7 +627,7 @@ static hsize_t diff_datum(
      *-------------------------------------------------------------------------
      */
     case H5T_OPAQUE:
-        h5difftrace("diff_datum H5T_OPAQUE\n");
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum H5T_OPAQUE");
         /* byte-by-byte comparison */
         for (u = 0; u < type_size; u++)
             nfound += character_compare_opt(mem1 + u, mem2 + u, index, rank, dims, acc, pos, opts, obj1, obj2, ph);
@@ -634,7 +643,7 @@ static hsize_t diff_datum(
          * compared, we convert both bit patterns to their corresponding
          * enumeration constant and do a string comparison
          */
-        h5difftrace("diff_datum H5T_ENUM\n");
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum H5T_ENUM");
         {
             char enum_name1[1024];
             char enum_name2[1024];
@@ -693,6 +702,7 @@ static hsize_t diff_datum(
      */
     case H5T_ARRAY:
         {
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum H5T_ARRAY");
             hid_t   memb_type = -1;
             hsize_t adims[H5S_MAX_RANK];
             int     ndims;
@@ -720,6 +730,7 @@ static hsize_t diff_datum(
      *-------------------------------------------------------------------------
      */
     case H5T_REFERENCE:
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum H5T_REFERENCE");
         iszero1 = all_zero(_mem1, H5Tget_size(m_type));
         iszero2 = all_zero(_mem2, H5Tget_size(m_type));
         if (iszero1 != iszero2) {
@@ -727,23 +738,285 @@ static hsize_t diff_datum(
             HGOTO_DONE (opts->err_stat);
         }
         else if (!iszero1 && !iszero2) {
-            /*-------------------------------------------------------------------------
-             * H5T_STD_REF_DSETREG
-             * Dataset region reference
-             *-------------------------------------------------------------------------
-             */
             hid_t obj1_id = -1;
             hid_t obj2_id = -1;
 
+            /*-------------------------------------------------------------------------
+             * H5T_STD_REF
+             * Reference
+             *-------------------------------------------------------------------------
+             */
             if (H5Tequal(m_type, H5T_STD_REF)) {
+                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum H5T_REFERENCE - H5T_STD_REF");
                 /* if (type_size == H5R_STD_REF_SIZE) */
-                H5TOOLS_INFO(H5E_tools_min_info_id_g, "NEW reference type");
+                hid_t region1_id = -1;
+                hid_t region2_id = -1;
+                H5R_ref_t *ref1_buf = (const H5R_ref_t *)_mem1;
+                H5R_ref_t *ref2_buf = (const H5R_ref_t *)_mem2;
+                H5O_type_t obj1_type;   /* Object type */
+                H5O_type_t obj2_type;   /* Object type */
+                H5R_type_t ref_type;   /* Reference type */
+
+                ref_type = H5Rget_type(ref1_buf);
+                switch (ref_type) {
+                    case H5R_OBJECT1:
+                        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "ref_type is H5R_OBJECT1");
+                        if (H5Rget_obj_type3(ref1_buf, H5P_DEFAULT, &obj1_type) < 0) {
+                            opts->err_stat = 1;
+                            H5TOOLS_INFO(H5E_tools_min_id_g, "H5Rget_obj_type3 object 1 failed");
+                        }
+                        if (H5Rget_obj_type3(ref2_buf, H5P_DEFAULT, &obj2_type) < 0) {
+                            opts->err_stat = 1;
+                            H5TOOLS_INFO(H5E_tools_min_id_g, "H5Rget_obj_type3 object 2 failed");
+                        }
+
+                        /* check object type */
+                        if (obj1_type != obj2_type) {
+                            parallel_print("Different object types referenced: <%s> and <%s>", obj1, obj2);
+                            opts->not_cmp = 1;
+                            HGOTO_DONE (opts->err_stat);
+                        }
+
+                        if((obj1_id = H5Ropen_object(ref1_buf, H5P_DEFAULT, H5P_DEFAULT)) < 0) {
+                            opts->err_stat = 1;
+                            H5TOOLS_INFO(H5E_tools_min_id_g, "H5Ropen_object object 1 failed");
+                        }
+                        if((obj2_id = H5Ropen_object(ref2_buf, H5P_DEFAULT, H5P_DEFAULT)) < 0) {
+                            opts->err_stat = 1;
+                            H5TOOLS_INFO(H5E_tools_min_id_g, "H5Ropen_object object 2 failed");
+                        }
+
+                        switch (obj1_type) {
+                            case H5O_TYPE_DATASET:
+                                nfound = diff_datasetid(obj1_id, obj2_id, NULL, NULL, opts);
+                                break;
+
+                            case H5O_TYPE_GROUP:
+                            case H5O_TYPE_NAMED_DATATYPE:
+                            case H5O_TYPE_MAP:
+                            case H5O_TYPE_UNKNOWN:
+                            case H5O_TYPE_NTYPES:
+                            default:
+                                if (opts->m_verbose)
+                                    parallel_print("Warning: Comparison not possible of object types referenced: <%s> and <%s>\n", obj1, obj2);
+                                opts->not_cmp = 1;
+                                break;
+                        } /* end switch */
+                        if(obj1_id >= 0)
+                            if(H5Oclose(obj1_id) < 0)
+                                H5TOOLS_INFO(H5E_tools_g, H5E_tools_min_id_g, "H5Oclose H5R_OBJECT1 failed");
+                        if(obj2_id >= 0)
+                            if(H5Oclose(obj2_id) < 0)
+                                H5TOOLS_INFO(H5E_tools_g, H5E_tools_min_id_g, "H5Oclose H5R_OBJECT1 failed");
+                        if(H5Rdestroy(ref2_buf) < 0)
+                            H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Rdestroy H5R_OBJECT1 failed");
+                        if(H5Rdestroy(ref1_buf) < 0)
+                            H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Rdestroy H5R_OBJECT1 failed");
+                        break;
+                    case H5R_DATASET_REGION1:
+                        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "ref_type is H5R_DATASET_REGION1");
+                        if((obj1_id = H5Ropen_object(ref1_buf, H5P_DEFAULT, H5P_DEFAULT)) >= 0) {
+                            if((obj2_id = H5Ropen_object(ref2_buf, H5P_DEFAULT, H5P_DEFAULT)) >= 0) {
+                                if((region1_id = H5Ropen_region(ref1_buf, H5P_DEFAULT, H5P_DEFAULT)) >= 0) {
+                                    if((region2_id = H5Ropen_region(ref2_buf, H5P_DEFAULT, H5P_DEFAULT)) >= 0) {
+                                        nfound = diff_region(obj1_id, obj2_id, region1_id, region2_id, opts);
+                                        if(H5Sclose(region2_id) < 0)
+                                            H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Sclose H5R_DATASET_REGION1 failed");
+                                    }
+                                    if(H5Sclose(region1_id) < 0)
+                                        H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Sclose H5R_DATASET_REGION1 failed");
+                                }
+                                if(H5Oclose(obj2_id) < 0)
+                                    H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Oclose H5R_DATASET_REGION1 failed");
+                            }
+                            else {
+                                H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Ropen_object H5R_DATASET_REGION1 failed");
+                            }
+                            if(H5Oclose(obj1_id) < 0)
+                                H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Oclose H5R_DATASET_REGION1 failed");
+                        }
+                        else {
+                            H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Ropen_object H5R_DATASET_REGION1 failed");
+                        }
+                        if(H5Rdestroy(ref2_buf) < 0)
+                            H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Rdestroy H5R_DATASET_REGION1 failed");
+                        if(H5Rdestroy(ref1_buf) < 0)
+                            H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Rdestroy H5R_DATASET_REGION1 failed");
+                        break;
+                    case H5R_OBJECT2:
+                        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "ref_type is H5R_OBJECT2");
+                        if (H5Rget_obj_type3(ref1_buf, H5P_DEFAULT, &obj1_type) < 0) {
+                            opts->err_stat = 1;
+                            H5TOOLS_INFO(H5E_tools_min_id_g, "H5Rget_obj_type3 object 1 failed");
+                        }
+                        if (H5Rget_obj_type3(ref2_buf, H5P_DEFAULT, &obj2_type) < 0) {
+                            opts->err_stat = 1;
+                            H5TOOLS_INFO(H5E_tools_min_id_g, "H5Rget_obj_type3 object 2 failed");
+                        }
+
+                        /* check object type */
+                        if (obj1_type != obj2_type) {
+                            parallel_print("Different object types referenced: <%s> and <%s>", obj1, obj2);
+                            opts->not_cmp = 1;
+                            HGOTO_DONE (opts->err_stat);
+                        }
+
+                        if((obj1_id = H5Ropen_object(ref1_buf, H5P_DEFAULT, H5P_DEFAULT)) < 0) {
+                            opts->err_stat = 1;
+                            H5TOOLS_INFO(H5E_tools_min_id_g, "H5Ropen_object object 1 failed");
+                        }
+                        if((obj2_id = H5Ropen_object(ref2_buf, H5P_DEFAULT, H5P_DEFAULT)) < 0) {
+                            opts->err_stat = 1;
+                            H5TOOLS_INFO(H5E_tools_min_id_g, "H5Ropen_object object 2 failed");
+                        }
+
+                        switch (obj1_type) {
+                            case H5O_TYPE_DATASET:
+                                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "ref_type is H5R_OBJECT2 : DATASET");
+                                nfound = diff_datasetid(obj1_id, obj2_id, NULL, NULL, opts);
+                                break;
+
+                            case H5O_TYPE_GROUP:
+                                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "ref_type is H5R_OBJECT2 : GROUP");
+                                if (opts->m_verbose)
+                                    parallel_print("Warning: Comparison not possible of group object types referenced: <%s> and <%s>\n", obj1, obj2);
+                                opts->not_cmp = 1;
+                                break;
+
+                            case H5O_TYPE_NAMED_DATATYPE:
+                                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "ref_type is H5R_OBJECT2 : NAMED");
+                                if (opts->m_verbose)
+                                    parallel_print("Warning: Comparison not possible of named datatypes object types referenced: <%s> and <%s>\n", obj1, obj2);
+                                opts->not_cmp = 1;
+                                break;
+
+                            case H5O_TYPE_MAP:
+                            case H5O_TYPE_UNKNOWN:
+                            case H5O_TYPE_NTYPES:
+                            default:
+                                if (opts->m_verbose)
+                                    parallel_print("Warning: Comparison not possible of object types referenced: <%s> and <%s>\n", obj1, obj2);
+                                opts->not_cmp = 1;
+                                break;
+                        } /* end switch */
+                        if(obj1_id >= 0)
+                            if(H5Oclose(obj1_id) < 0)
+                                H5TOOLS_INFO(H5E_tools_g, H5E_tools_min_id_g, "H5Oclose H5R_OBJECT2 failed");
+                        if(obj2_id >= 0)
+                            if(H5Oclose(obj2_id) < 0)
+                                H5TOOLS_INFO(H5E_tools_g, H5E_tools_min_id_g, "H5Oclose H5R_OBJECT2 failed");
+                        if(H5Rdestroy(ref2_buf) < 0)
+                            H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Rdestroy H5R_OBJECT2 failed");
+                        if(H5Rdestroy(ref1_buf) < 0)
+                            H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Rdestroy H5R_OBJECT2 failed");
+                        break;
+                    case H5R_DATASET_REGION2:
+                        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "ref_type is H5R_DATASET_REGION2");
+
+                        /* if (obj_id < 0) - could mean that no reference was written do not throw failure */
+                        obj1_id = H5Ropen_object(ref1_buf, H5P_DEFAULT, H5P_DEFAULT);
+                        obj2_id = H5Ropen_object(ref2_buf, H5P_DEFAULT, H5P_DEFAULT);
+                        if((obj1_id  < 0) || (obj1_id  < 0))
+                            H5Epush2(H5tools_ERR_STACK_g, __FILE__, FUNC, __LINE__, H5tools_ERR_CLS_g, H5E_tools_g, H5E_tools_min_id_g,
+                                    "H5Ropen_object H5R_DATASET_REGION2 failed");
+                        else {
+                            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "open_region - H5R_DATASET_REGION2");
+                            if((region1_id = H5Ropen_region(ref1_buf, H5P_DEFAULT, H5P_DEFAULT)) >= 0) {
+                                if (h5tools_is_zero(ref1_buf, H5Tget_size(H5T_STD_REF))) {
+                                    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "NULL H5R_DATASET_REGION2");
+                                }
+                                else {
+                                    if((region2_id = H5Ropen_region(ref2_buf, H5P_DEFAULT, H5P_DEFAULT)) >= 0) {
+                                        if (h5tools_is_zero(ref2_buf, H5Tget_size(H5T_STD_REF))) {
+                                            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "NULL H5R_DATASET_REGION2");
+                                        }
+                                        else {
+                                            nfound = diff_region(obj1_id, obj2_id, region1_id, region2_id, opts);
+                                        }
+                                        if(H5Sclose(region2_id) < 0)
+                                            H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Sclose H5R_DATASET_REGION2 failed");
+                                    }
+                                    else
+                                        H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Ropen_region H5R_DATASET_REGION2 failed");
+                                } /* end else to if (h5tools_is_zero(... */
+                                if(H5Sclose(region1_id) < 0)
+                                    H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Sclose H5R_DATASET_REGION2 failed");
+                            }
+                            else
+                                H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Ropen_region H5R_DATASET_REGION2 failed");
+                            if (obj1_id >= 0)
+                                if(H5Dclose(obj1_id) < 0)
+                                    H5TOOLS_INFO(H5E_tools_g, H5E_tools_min_id_g, "H5Dclose H5R_DATASET_REGION2 failed");
+                            if (obj2_id >= 0)
+                                if(H5Dclose(obj2_id) < 0)
+                                    H5TOOLS_INFO(H5E_tools_g, H5E_tools_min_id_g, "H5Dclose H5R_DATASET_REGION2 failed");
+                            if(H5Rdestroy(ref1_buf) < 0)
+                                H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Rdestroy H5R_DATASET_REGION2 failed");
+                            if(H5Rdestroy(ref2_buf) < 0)
+                                H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Rdestroy H5R_DATASET_REGION2 failed");
+                        }
+                        break;
+                    case H5R_ATTR:
+                        {
+                            char       name1[ATTR_NAME_MAX];
+                            char       name2[ATTR_NAME_MAX];
+
+                            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "ref_type is H5R_ATTR");
+                            if((obj1_id = H5Ropen_attr(ref1_buf, H5P_DEFAULT, H5P_DEFAULT)) < 0) {
+                                parallel_print("Warning: Cannot open referenced attribute: attribute 1\n");
+                                H5TOOLS_INFO(H5E_tools_min_id_g, "H5Ropen_attr object 1 failed");
+                            }
+                            if((obj2_id = H5Ropen_attr(ref2_buf, H5P_DEFAULT, H5P_DEFAULT)) < 0) {
+                                parallel_print("Warning: Cannot open referenced attribute: attribute 2\n");
+                                H5TOOLS_INFO(H5E_tools_min_id_g, "H5Ropen_attr object 2 failed");
+                            }
+
+                            if((obj1_id  < 0) || (obj1_id  < 0))
+                                H5Epush2(H5tools_ERR_STACK_g, __FILE__, FUNC, __LINE__, H5tools_ERR_CLS_g, H5E_tools_g, H5E_tools_min_id_g,
+                                        "H5Ropen_attr H5R_ATTR failed");
+                            else {
+                                /* get name */
+                                if(H5Aget_name(obj1_id, (size_t)ATTR_NAME_MAX, name1) < 0)
+                                    H5TOOLS_GOTO_ERROR(FAIL, H5E_tools_min_id_g, "H5Aget_name first attribute failed");
+                                /* get name */
+                                if(H5Aget_name(obj2_id, (size_t)ATTR_NAME_MAX, name2) < 0)
+                                    H5TOOLS_GOTO_ERROR(FAIL, H5E_tools_min_id_g, "H5Aget_name second attribute failed");
+
+                                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "H5R_ATTR diff_attr_data - name1=%s, name2=%s", name1, name2);
+                                nfound = diff_attr_data(obj1_id, obj2_id, name1, name2, NULL, NULL, opts);
+                            }
+
+                            if(obj1_id >= 0)
+                                    if(H5Aclose(obj1_id) < 0)
+                                        H5TOOLS_INFO(H5E_tools_g, H5E_tools_min_id_g, "H5Aclose H5R_ATTR failed");
+                            if(obj2_id >= 0)
+                                    if(H5Aclose(obj2_id) < 0)
+                                        H5TOOLS_INFO(H5E_tools_g, H5E_tools_min_id_g, "H5Aclose H5R_ATTR failed");
+                            if(H5Rdestroy(ref2_buf) < 0)
+                                H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Rdestroy H5R_ATTR failed");
+                            if(H5Rdestroy(ref1_buf) < 0)
+                                H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Rdestroy H5R_ATTR failed");
+                        }
+                        break;
+                    case H5R_BADTYPE:
+                    case H5R_MAXTYPE:
+                    default:
+                        break;
+                } /* end switch */
+                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum H5T_REFERENCE - H5T_STD_REF complete nfound:%d - errstat:%d", nfound, opts->err_stat);
             }
+            /*-------------------------------------------------------------------------
+             * H5T_STD_REF_DSETREG
+             * Dataset region reference
+             *-------------------------------------------------------------------------
+             */
             else if (H5Tequal(m_type, H5T_STD_REF_DSETREG)) {
                 /* if (type_size == H5R_DSET_REG_REF_BUF_SIZE) */
                 hid_t region1_id = -1;
                 hid_t region2_id = -1;
 
+                H5TOOLS_INFO(H5E_tools_min_info_id_g, "H5T_STD_REF_DSETREG reference type");
+
                 if ((obj1_id = H5Rdereference2(container1_id, H5P_DEFAULT, H5R_DATASET_REGION, _mem1)) < 0) {
                     opts->err_stat = 1;
                     H5TOOLS_INFO(H5E_tools_min_id_g, "H5Rdereference2 object 1 failed");
@@ -779,6 +1052,8 @@ static hsize_t diff_datum(
                 H5O_type_t obj1_type;
                 H5O_type_t obj2_type;
 
+                H5TOOLS_INFO(H5E_tools_min_info_id_g, "H5T_STD_REF_OBJ reference type");
+
                 if (H5Rget_obj_type2(container1_id, H5R_OBJECT, _mem1, &obj1_type) < 0) {
                     opts->err_stat = 1;
                     H5TOOLS_INFO(H5E_tools_min_id_g, "H5Rget_obj_type2 object 1 failed");
@@ -809,9 +1084,7 @@ static hsize_t diff_datum(
                     nfound = diff_datasetid(obj1_id, obj2_id, NULL, NULL, opts);
                 else {
                     if (opts->m_verbose)
-                        parallel_print(
-                                "Warning: Comparison not possible of object types referenced: <%s> and <%s>\n",
-                                obj1, obj2);
+                        parallel_print("Warning: Comparison not possible of object types referenced: <%s> and <%s>\n", obj1, obj2);
                     opts->not_cmp = 1;
                 }
 
@@ -819,6 +1092,7 @@ static hsize_t diff_datum(
                 H5Oclose(obj2_id);
             }/*object reference*/
         }/*is zero*/
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum H5T_REFERENCE complete");
         break;
 
     /*-------------------------------------------------------------------------
@@ -829,6 +1103,7 @@ static hsize_t diff_datum(
         {
             hid_t memb_type = -1;
 
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum H5T_VLEN");
             /* get the VL sequences's base datatype for each element */
             memb_type = H5Tget_super(m_type);
             size = H5Tget_size(memb_type);
@@ -849,6 +1124,7 @@ static hsize_t diff_datum(
      *-------------------------------------------------------------------------
      */
     case H5T_INTEGER:
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum H5T_INTEGER");
         type_sign = H5Tget_sign(m_type);
         /*-------------------------------------------------------------------------
          * H5T_NATIVE_SCHAR
@@ -1467,6 +1743,7 @@ static hsize_t diff_datum(
          * H5T_NATIVE_FLOAT
          *-------------------------------------------------------------------------
          */
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum H5T_FLOAT");
         if (type_size == 4) {
             float temp1_float;
             float temp2_float;
@@ -1947,8 +2224,10 @@ static hsize_t diff_datum(
 done:
     opts->err_stat = opts->err_stat | ret_value;
 
-    h5diffdebug3("diff_datum finish:%d - errstat:%d\n", nfound, opts->err_stat);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datum finish:%d - errstat:%d", nfound, opts->err_stat);
 
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return nfound;
 }
 
@@ -2025,7 +2304,7 @@ void print_points(int i, hsize_t *ptdata, int ndims) {
 static hsize_t diff_region(hid_t obj1_id, hid_t obj2_id, hid_t region1_id, hid_t region2_id, diff_opt_t *opts)
 
 {
-    hsize_t  ret_value = 0;
+    H5TOOLS_ERR_INIT(hsize_t, 0)
     hssize_t nblocks1, npoints1;
     hssize_t nblocks2, npoints2;
     hsize_t  alloc_size;
@@ -2037,6 +2316,9 @@ static hsize_t diff_region(hid_t obj1_id, hid_t obj2_id, hid_t region1_id, hid_t
     hsize_t  nfound_b = 0; /* block differences found */
     hsize_t  nfound_p = 0; /* point differences found */
 
+    H5TOOLS_PUSH_STACK();
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_region start");
+
     ndims1 = H5Sget_simple_extent_ndims(region1_id);
     ndims2 = H5Sget_simple_extent_ndims(region2_id);
 
@@ -2052,6 +2334,8 @@ static hsize_t diff_region(hid_t obj1_id, hid_t obj2_id, hid_t region1_id, hid_t
         npoints1 = H5Sget_select_elem_npoints(region1_id);
         npoints2 = H5Sget_select_elem_npoints(region2_id);
     } H5E_END_TRY;
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_region blocks: 1=%ld-2=%ld", nblocks1, nblocks2);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_region points: 1=%ld-2=%ld", npoints1, npoints2);
 
     if (nblocks1 != nblocks2 || npoints1 != npoints2 || ndims1 != ndims2) {
         opts->not_cmp = 1;
@@ -2063,6 +2347,7 @@ static hsize_t diff_region(hid_t obj1_id, hid_t obj2_id, hid_t region1_id, hid_t
      *-------------------------------------------------------------------------
      */
     if (nblocks1 > 0) {
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "region compare blocks");
         HDassert(ndims1 > 0);
         alloc_size = (hsize_t) nblocks1 * (unsigned) ndims1 * 2 * sizeof(ptdata1[0]);
         HDassert(alloc_size == (hsize_t)((size_t )alloc_size)); /*check for overflow*/
@@ -2127,6 +2412,7 @@ static hsize_t diff_region(hid_t obj1_id, hid_t obj2_id, hid_t region1_id, hid_t
      *-------------------------------------------------------------------------
      */
     if (npoints1 > 0) {
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "region compare points");
         alloc_size = (hsize_t) npoints1 * (unsigned) ndims1 * sizeof(ptdata1[0]);
         HDassert(alloc_size == (hsize_t)((size_t )alloc_size)); /*check for overflow*/
 
@@ -2191,6 +2477,7 @@ static hsize_t diff_region(hid_t obj1_id, hid_t obj2_id, hid_t region1_id, hid_t
 
                 parallel_print(")");
             }
+            parallel_print("\n");
 #endif
 
             HDfree(ptdata1);
@@ -2203,6 +2490,8 @@ static hsize_t diff_region(hid_t obj1_id, hid_t obj2_id, hid_t region1_id, hid_t
     ret_value = nfound_p + nfound_b;
 
 done:
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit with diffs:%d", ret_value);
+    H5TOOLS_POP_STACK();
     return ret_value;
 }
 
@@ -2218,13 +2507,15 @@ done:
 static hsize_t character_compare(char *mem1, char *mem2, hsize_t i, size_t u,
         int rank, hsize_t *dims, hsize_t *acc, hsize_t *pos, diff_opt_t *opts, const char *obj1, const char *obj2, int *ph)
 {
+    H5TOOLS_ERR_INIT(int, 0)
     hsize_t nfound = 0; /* differences found */
     char    temp1_uchar;
     char    temp2_uchar;
 
+    H5TOOLS_PUSH_STACK();
     HDmemcpy(&temp1_uchar, mem1, sizeof(unsigned char));
     HDmemcpy(&temp2_uchar, mem2, sizeof(unsigned char));
-    h5diffdebug3("character_compare start %d=%d\n",temp1_uchar,temp2_uchar);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "character_compare start %d=%d",temp1_uchar,temp2_uchar);
 
     if (temp1_uchar != temp2_uchar) {
         if (print_data(opts)) {
@@ -2237,8 +2528,10 @@ static hsize_t character_compare(char *mem1, char *mem2, hsize_t i, size_t u,
         }
         nfound++;
     }
-    h5difftrace("character_compare finish\n");
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "character_compare finish");
 
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit: %d", nfound);
+    H5TOOLS_POP_STACK();
     return nfound;
 }
 
@@ -2263,7 +2556,6 @@ static hsize_t character_compare_opt(unsigned char *mem1, unsigned char *mem2,
     HDmemcpy(&temp1_uchar, mem1, sizeof(unsigned char));
     HDmemcpy(&temp2_uchar, mem2, sizeof(unsigned char));
 
-    h5difftrace("character_compare_opt start\n");
     /* -d and !-p */
 
     if (opts->d && !opts->p) {
@@ -2307,7 +2599,7 @@ static hsize_t character_compare_opt(unsigned char *mem1, unsigned char *mem2,
             parallel_print(I_FORMAT, temp1_uchar, temp2_uchar, PDIFF(temp1_uchar, temp2_uchar));
         }
         nfound++;
-    } h5difftrace("character_compare_opt finish\n");
+    }
 
     return nfound;
 }
@@ -2335,8 +2627,6 @@ static hsize_t diff_float(unsigned char *mem1, unsigned char *mem2,
     hbool_t isnan1 = FALSE;
     hbool_t isnan2 = FALSE;
 
-    h5difftrace("diff_float start\n");
-
     /*-------------------------------------------------------------------------
      * -d and !-p
      *-------------------------------------------------------------------------
@@ -2520,7 +2810,6 @@ static hsize_t diff_float(unsigned char *mem1, unsigned char *mem2,
                 return nfound;
         } /* nelmts */
     }
-    h5difftrace("diff_float finish\n");
 
     return nfound;
 }
@@ -2548,7 +2837,6 @@ static hsize_t diff_double(unsigned char *mem1, unsigned char *mem2,
     hbool_t isnan1 = FALSE;
     hbool_t isnan2 = FALSE;
 
-    h5difftrace("diff_double start\n");
     /*-------------------------------------------------------------------------
      * -d and !-p
      *-------------------------------------------------------------------------
@@ -2731,7 +3019,6 @@ static hsize_t diff_double(unsigned char *mem1, unsigned char *mem2,
                 return nfound;
         } /* nelmts */
     }
-    h5difftrace("diff_double finish\n");
 
     return nfound;
 }
@@ -2769,8 +3056,6 @@ static hsize_t diff_ldouble(unsigned char *mem1,
     hbool_t     isnan1 = FALSE;
     hbool_t     isnan2 = FALSE;
 
-    h5difftrace("diff_ldouble start\n");
-
     /*-------------------------------------------------------------------------
      * -d and !-p
      *-------------------------------------------------------------------------
@@ -2949,7 +3234,6 @@ static hsize_t diff_ldouble(unsigned char *mem1,
                 return nfound;
         } /* nelmts */
     }
-    h5difftrace("diff_ldouble finish\n");
 
     return nfound;
 }
@@ -2976,7 +3260,6 @@ static hsize_t diff_schar(unsigned char *mem1, unsigned char *mem2,
     double  per;
     hbool_t both_zero;
 
-    h5difftrace("diff_schar start\n");
     /* -d and !-p */
     if (opts->d && !opts->p) {
         for (i = 0; i < nelmts; i++) {
@@ -3077,7 +3360,6 @@ static hsize_t diff_schar(unsigned char *mem1, unsigned char *mem2,
                 return nfound;
         } /* nelmts */
     }
-    h5difftrace("diff_schar finish\n");
 
     return nfound;
 }
@@ -3102,7 +3384,6 @@ static hsize_t diff_uchar(unsigned char *mem1, unsigned char *mem2,
     double        per;
     hbool_t       both_zero;
 
-    h5difftrace("diff_uchar start\n");
     /* -d and !-p */
     if (opts->d && !opts->p) {
         for (i = 0; i < nelmts; i++) {
@@ -3203,7 +3484,6 @@ static hsize_t diff_uchar(unsigned char *mem1, unsigned char *mem2,
                 return nfound;
         } /* nelmts */
     }
-    h5difftrace("diff_uchar finish\n");
 
     return nfound;
 }
@@ -3228,7 +3508,6 @@ static hsize_t diff_short(unsigned char *mem1, unsigned char *mem2,
     double  per;
     hbool_t both_zero;
 
-    h5difftrace("diff_short start\n");
     /* -d and !-p */
     if (opts->d && !opts->p) {
         for (i = 0; i < nelmts; i++) {
@@ -3329,7 +3608,6 @@ static hsize_t diff_short(unsigned char *mem1, unsigned char *mem2,
                 return nfound;
         } /* nelmts */
     }
-    h5difftrace("diff_short finish\n");
 
     return nfound;
 }
@@ -3355,7 +3633,6 @@ static hsize_t diff_ushort(unsigned char *mem1, unsigned char *mem2,
     double         per;
     hbool_t        both_zero;
 
-    h5difftrace("diff_ushort start\n");
     /* -d and !-p */
     if (opts->d && !opts->p) {
         for (i = 0; i < nelmts; i++) {
@@ -3456,7 +3733,6 @@ static hsize_t diff_ushort(unsigned char *mem1, unsigned char *mem2,
                 return nfound;
         } /* nelmts */
     }
-    h5difftrace("diff_ushort finish\n");
 
     return nfound;
 }
@@ -3481,7 +3757,6 @@ static hsize_t diff_int(unsigned char *mem1, unsigned char *mem2,
     double  per;
     hbool_t both_zero;
 
-    h5difftrace("diff_int start\n");
     /* -d and !-p */
     if (opts->d && !opts->p) {
         for (i = 0; i < nelmts; i++) {
@@ -3583,7 +3858,6 @@ static hsize_t diff_int(unsigned char *mem1, unsigned char *mem2,
         } /* nelmts */
 
     }
-    h5difftrace("diff_int finish\n");
     return nfound;
 }
 
@@ -3607,7 +3881,6 @@ static hsize_t diff_uint(unsigned char *mem1, unsigned char *mem2,
     double per;
     hbool_t both_zero;
 
-    h5difftrace("diff_uint start\n");
     /* -d and !-p */
     if (opts->d && !opts->p) {
         for (i = 0; i < nelmts; i++) {
@@ -3709,7 +3982,6 @@ static hsize_t diff_uint(unsigned char *mem1, unsigned char *mem2,
                 return nfound;
         } /* nelmts */
     }
-    h5difftrace("diff_uint finish\n");
 
     return nfound;
 }
@@ -3734,7 +4006,6 @@ static hsize_t diff_long(unsigned char *mem1, unsigned char *mem2,
     double per;
     hbool_t both_zero;
 
-    h5difftrace("diff_long start\n");
     /* -d and !-p */
     if (opts->d && !opts->p) {
         for (i = 0; i < nelmts; i++) {
@@ -3837,7 +4108,6 @@ static hsize_t diff_long(unsigned char *mem1, unsigned char *mem2,
                 return nfound;
         } /* nelmts */
     }
-    h5difftrace("diff_long finish\n");
 
     return nfound;
 }
@@ -3862,8 +4132,6 @@ static hsize_t diff_ulong(unsigned char *mem1, unsigned char *mem2,
     double        per;
     hbool_t       both_zero;
 
-    h5difftrace("diff_ulong start\n");
-
     /* -d and !-p */
     if (opts->d && !opts->p) {
         for (i = 0; i < nelmts; i++) {
@@ -3967,7 +4235,6 @@ static hsize_t diff_ulong(unsigned char *mem1, unsigned char *mem2,
                 return nfound;
         } /* nelmts */
     }
-    h5difftrace("diff_ulong finish\n");
 
     return nfound;
 }
@@ -3992,7 +4259,6 @@ static hsize_t diff_llong(unsigned char *mem1, unsigned char *mem2,
     double    per;
     hbool_t   both_zero;
 
-    h5difftrace("diff_llong start\n");
     /* -d and !-p */
     if (opts->d && !opts->p) {
         for (i = 0; i < nelmts; i++) {
@@ -4094,7 +4360,6 @@ static hsize_t diff_llong(unsigned char *mem1, unsigned char *mem2,
                 return nfound;
         } /* nelmts */
     }
-    h5difftrace("diff_llong finish\n");
 
     return nfound;
 }
@@ -4120,7 +4385,6 @@ static hsize_t diff_ullong(unsigned char *mem1, unsigned char *mem2,
     double             per;
     hbool_t            both_zero;
 
-    h5difftrace("diff_ullong start\n");
     /* -d and !-p */
     if (opts->d && !opts->p) {
         for (i = 0; i < nelmts; i++) {
@@ -4226,7 +4490,6 @@ static hsize_t diff_ullong(unsigned char *mem1, unsigned char *mem2,
                 return nfound;
         } /* nelmts */
     }
-    h5difftrace("diff_ullong finish\n");
 
     return nfound;
 }
@@ -4240,13 +4503,14 @@ static hsize_t diff_ullong(unsigned char *mem1, unsigned char *mem2,
 static
 int ull2float(unsigned long long ull_value, float *f_value)
 {
-    int            ret_value = SUCCEED;
+    H5TOOLS_ERR_INIT(int, SUCCEED)
     hid_t          dxpl_id = -1;
     unsigned char *buf = NULL;
     size_t         src_size;
     size_t         dst_size;
 
-    h5difftrace("ull2float start\n");
+    H5TOOLS_PUSH_STACK();
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "ull2float start");
     if ((dxpl_id = H5Pcreate(H5P_DATASET_XFER)) < 0)
         H5TOOLS_GOTO_ERROR(FAIL, H5E_tools_min_id_g, "H5Pcreate failed");
 
@@ -4271,8 +4535,10 @@ done:
     if (buf)
         HDfree(buf);
 
-    h5difftrace("ull2float finish\n");
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "ull2float finish");
 
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return ret_value;
 }
 
@@ -4283,7 +4549,6 @@ done:
  *-------------------------------------------------------------------------
  */
 static hbool_t equal_double(double value, double expected, diff_opt_t *opts) {
-    h5difftrace("equal_double start\n");
     if (opts->do_nans) {
         /*-------------------------------------------------------------------------
         * detect NaNs
@@ -4314,8 +4579,6 @@ static hbool_t equal_double(double value, double expected, diff_opt_t *opts) {
         if (ABS((value-expected)) < DBL_EPSILON)
             return TRUE;
 
-    h5difftrace("equal_double finish\n");
-
     return FALSE;
 }
 
@@ -4330,7 +4593,6 @@ static hbool_t equal_double(double value, double expected, diff_opt_t *opts) {
 static
 hbool_t equal_ldouble(long double value, long double expected, diff_opt_t *opts)
 {
-    h5difftrace("equal_ldouble start\n");
     if (opts->do_nans) {
         /*-------------------------------------------------------------------------
          * detect NaNs
@@ -4361,8 +4623,6 @@ hbool_t equal_ldouble(long double value, long double expected, diff_opt_t *opts)
         if (ABS((value-expected)) < DBL_EPSILON)
             return TRUE;
 
-    h5difftrace("equal_ldouble finish\n");
-
     return FALSE;
 }
 
@@ -4375,7 +4635,6 @@ hbool_t equal_ldouble(long double value, long double expected, diff_opt_t *opts)
  *-------------------------------------------------------------------------
  */
 static hbool_t equal_float(float value, float expected, diff_opt_t *opts) {
-    h5difftrace("equal_float start\n");
     if (opts->do_nans) {
         /*-------------------------------------------------------------------------
         * detect NaNs
@@ -4406,8 +4665,6 @@ static hbool_t equal_float(float value, float expected, diff_opt_t *opts) {
         if (ABS( (value-expected) ) < FLT_EPSILON)
             return TRUE;
 
-    h5difftrace("equal_float finish\n");
-
     return FALSE;
 }
 
@@ -4423,7 +4680,6 @@ static hbool_t my_isnan(dtype_t type, void *val) {
     hbool_t retval = FALSE;
     char s[256];
 
-    h5difftrace("my_isnan start\n");
     if (FLT_FLOAT == type) {
         float x;
 
@@ -4483,8 +4739,6 @@ static hbool_t my_isnan(dtype_t type, void *val) {
         }
     }
 
-    h5difftrace("my_isnan finish\n");
-
     return retval;
 }
 
diff --git a/tools/lib/h5diff_attr.c b/tools/lib/h5diff_attr.c
index cd906af..bd66567 100644
--- a/tools/lib/h5diff_attr.c
+++ b/tools/lib/h5diff_attr.c
@@ -139,10 +139,10 @@ static void table_attr_mark_exist(unsigned *exist, char *name, table_attrs_t *ta
  *------------------------------------------------------------------------*/
 static herr_t build_match_list_attrs(hid_t loc1_id, hid_t loc2_id, table_attrs_t ** table_out,  diff_opt_t *opts)
 {
-    int        ret_value = 0;
+    H5TOOLS_ERR_INIT(herr_t, 0)
     H5O_info_t oinfo1, oinfo2;    /* Object info */
-    hid_t      attr1_id = -1;     /* attr ID */
-    hid_t      attr2_id = -1;     /* attr ID */
+    hid_t      attr1_id = H5I_INVALID_HID;     /* attr ID */
+    hid_t      attr2_id = H5I_INVALID_HID;     /* attr ID */
     size_t     curr1 = 0;
     size_t     curr2 = 0;
     unsigned   infile[2];
@@ -152,12 +152,17 @@ static herr_t build_match_list_attrs(hid_t loc1_id, hid_t loc2_id, table_attrs_t
     unsigned   i;
     table_attrs_t *table_lp = NULL;
 
-    h5difftrace("build_match_list_attrs start\n");
+    H5TOOLS_PUSH_STACK();
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "build_match_list_attrs start - errstat:%d", opts->err_stat);
 
-    if(H5Oget_info2(loc1_id, &oinfo1, H5O_INFO_NUM_ATTRS) < 0)
+    if(H5Oget_info2(loc1_id, &oinfo1, H5O_INFO_NUM_ATTRS) < 0) {
         H5TOOLS_GOTO_ERROR(FAIL, H5E_tools_min_id_g, "H5Oget_info first object failed");
-    if(H5Oget_info2(loc2_id, &oinfo2, H5O_INFO_NUM_ATTRS) < 0)
+    }
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "H5Oget_info2 loc1id=%d", oinfo1.num_attrs);
+    if(H5Oget_info2(loc2_id, &oinfo2, H5O_INFO_NUM_ATTRS) < 0) {
         H5TOOLS_GOTO_ERROR(FAIL, H5E_tools_min_id_g, "H5Oget_info second object failed");
+    }
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "H5Oget_info2 loc2id=%d", oinfo2.num_attrs);
 
     table_attrs_init(&table_lp);
     if (table_lp == NULL)
@@ -167,8 +172,8 @@ static herr_t build_match_list_attrs(hid_t loc1_id, hid_t loc2_id, table_attrs_t
      * build the list
      */
     while(curr1 < oinfo1.num_attrs && curr2 < oinfo2.num_attrs) {
-        h5diffdebug3("build_match_list_attrs 1: %ld - %ld\n", curr1, oinfo1.num_attrs);
-        h5diffdebug3("build_match_list_attrs 2: %ld - %ld\n", curr2, oinfo2.num_attrs);
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "build_match_list_attrs 1: %ld - %ld", curr1, oinfo1.num_attrs);
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "build_match_list_attrs 2: %ld - %ld", curr2, oinfo2.num_attrs);
 
         /*------------------
         * open attribute1 */
@@ -222,7 +227,7 @@ static herr_t build_match_list_attrs(hid_t loc1_id, hid_t loc2_id, table_attrs_t
     infile[0] = 1;
     infile[1] = 0;
     while(curr1 < oinfo1.num_attrs) {
-        h5diffdebug3("build_match_list_attrs 1: %ld - %ld\n", curr1, oinfo1.num_attrs);
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "build_match_list_attrs 1: %ld - %ld", curr1, oinfo1.num_attrs);
 
         /*------------------
         * open attribute1 */
@@ -231,7 +236,7 @@ static herr_t build_match_list_attrs(hid_t loc1_id, hid_t loc2_id, table_attrs_t
         /* get name */
         if(H5Aget_name(attr1_id, (size_t)ATTR_NAME_MAX, name1) < 0)
             H5TOOLS_GOTO_ERROR(FAIL, H5E_tools_min_id_g, "H5Aget_name first attribute failed");
-        h5diffdebug2("build_match_list_attrs #1 name - %s\n", name1);
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "build_match_list_attrs #1 name - %s", name1);
 
         table_attr_mark_exist(infile, name1, table_lp);
         table_lp->nattrs_only1++;
@@ -246,7 +251,7 @@ static herr_t build_match_list_attrs(hid_t loc1_id, hid_t loc2_id, table_attrs_t
     infile[0] = 0;
     infile[1] = 1;
     while(curr2 < oinfo2.num_attrs) {
-        h5diffdebug3("build_match_list_attrs 2: %ld - %ld\n", curr2, oinfo2.num_attrs);
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "build_match_list_attrs 2: %ld - %ld", curr2, oinfo2.num_attrs);
         /*------------------
         * open attribute2 */
         if((attr2_id = H5Aopen_by_idx(loc2_id, ".", H5_INDEX_NAME, H5_ITER_INC, (hsize_t)curr2, H5P_DEFAULT, H5P_DEFAULT)) < 0)
@@ -254,7 +259,7 @@ static herr_t build_match_list_attrs(hid_t loc1_id, hid_t loc2_id, table_attrs_t
         /* get name */
         if(H5Aget_name(attr2_id, (size_t)ATTR_NAME_MAX, name2) < 0)
             H5TOOLS_GOTO_ERROR(FAIL, H5E_tools_min_id_g, "H5Aget_name second attribute failed");
-        h5diffdebug2("build_match_list_attrs #2 name - %s\n", name2);
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "build_match_list_attrs #2 name - %s", name2);
 
         table_attr_mark_exist(infile, name2, table_lp);
         table_lp->nattrs_only2++;
@@ -294,39 +299,32 @@ done:
         H5Aclose(attr2_id);
     } H5E_END_TRY;
 
-    h5diffdebug2("build_match_list_attrs end - errstat:%d\n", opts->err_stat);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "build_match_list_attrs end - errstat:%d", opts->err_stat);
 
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return ret_value;
 }
 
 /*-------------------------------------------------------------------------
- * Function: diff_attr
+ * Function: diff_attr_data
  *
- * Purpose:  compare attributes located in LOC1_ID and LOC2_ID, which are
- *           obtained either from
- *               loc_id = H5Gopen2(fid, name, H5P_DEFAULT);
- *               loc_id = H5Dopen2(fid, name);
- *               loc_id = H5Topen2(fid, name, H5P_DEFAULT);
+ * Purpose:  compare attribute data located in attr1_id and attr2_id, which are
+ *           obtained from open attributes
  *
  * Return:   number of differences found
  *-------------------------------------------------------------------------
  */
 
-hsize_t diff_attr(hid_t loc1_id,
-                  hid_t loc2_id,
-                  const char *path1,
-                  const char *path2,
-                  diff_opt_t *opts)
+hsize_t diff_attr_data(hid_t attr1_id, hid_t attr2_id, const char *name1, const char *name2, const char *path1, const char *path2, diff_opt_t *opts)
 {
-    int        ret_value = opts->err_stat;
-    hid_t      attr1_id = -1;     /* attr ID */
-    hid_t      attr2_id = -1;     /* attr ID */
-    hid_t      space1_id = -1;    /* space ID */
-    hid_t      space2_id = -1;    /* space ID */
-    hid_t      ftype1_id = -1;    /* file data type ID */
-    hid_t      ftype2_id = -1;    /* file data type ID */
-    hid_t      mtype1_id = -1;    /* memory data type ID */
-    hid_t      mtype2_id = -1;    /* memory data type ID */
+    H5TOOLS_ERR_INIT(int, opts->err_stat)
+    hid_t      space1_id = H5I_INVALID_HID;    /* space ID */
+    hid_t      space2_id = H5I_INVALID_HID;    /* space ID */
+    hid_t      ftype1_id = H5I_INVALID_HID;    /* file data type ID */
+    hid_t      ftype2_id = H5I_INVALID_HID;    /* file data type ID */
+    hid_t      mtype1_id = H5I_INVALID_HID;    /* memory data type ID */
+    hid_t      mtype2_id = H5I_INVALID_HID;    /* memory data type ID */
     size_t     msize1;            /* memory size of memory type */
     size_t     msize2;            /* memory size of memory type */
     void       *buf1 = NULL;      /* data buffer */
@@ -338,36 +336,243 @@ hsize_t diff_attr(hid_t loc1_id,
     int        rank2;             /* rank of dataset */
     hsize_t    dims1[H5S_MAX_RANK];    /* dimensions of dataset */
     hsize_t    dims2[H5S_MAX_RANK];    /* dimensions of dataset */
-    char       *name1 = NULL;
-    char       *name2 = NULL;
     char       np1[512];
     char       np2[512];
     unsigned   u;                 /* Local index variable */
     hsize_t    nfound = 0;
-    hsize_t    nfound_total = 0;
     int       j;
 
+    H5TOOLS_PUSH_STACK();
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_attr_data start - errstat:%d", opts->err_stat);
+
+    /* get the datatypes  */
+    if((ftype1_id = H5Aget_type(attr1_id)) < 0)
+        H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_type first attribute failed");
+    if((ftype2_id = H5Aget_type(attr2_id)) < 0)
+        H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_type second attribute failed");
+
+    if (H5Tget_class(ftype1_id) == H5T_REFERENCE) {
+        if((mtype1_id = H5Tcopy(H5T_STD_REF)) < 0)
+            H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tcopy(H5T_STD_REF) first attribute ftype failed");
+    }
+    else {
+        if((mtype1_id = H5Tget_native_type(ftype1_id, H5T_DIR_DEFAULT)) < 0)
+            H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tget_native_type first attribute ftype failed");
+    }
+    if (H5Tget_class(ftype2_id) == H5T_REFERENCE) {
+        if((mtype2_id = H5Tcopy(H5T_STD_REF)) < 0)
+            H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tcopy(H5T_STD_REF) second attribute ftype failed");
+    }
+    else {
+        if((mtype2_id = H5Tget_native_type(ftype2_id, H5T_DIR_DEFAULT)) < 0)
+            H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tget_native_type second attribute ftype failed");
+    }
+    if((msize1 = H5Tget_size(mtype1_id)) == 0)
+        H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tget_size first attribute mtype failed");
+    if((msize2 = H5Tget_size(mtype2_id)) == 0)
+        H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tget_size second attribute mtype failed");
+
+    /* get the dataspace   */
+    if((space1_id = H5Aget_space(attr1_id)) < 0)
+        H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_space first attribute failed");
+    if((space2_id = H5Aget_space(attr2_id)) < 0)
+        H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_space second attribute failed");
+
+    /* get dimensions  */
+    if((rank1 = H5Sget_simple_extent_dims(space1_id, dims1, NULL)) < 0)
+        H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Sget_simple_extent_dims first attribute failed");
+    if((rank2 = H5Sget_simple_extent_dims(space2_id, dims2, NULL)) < 0)
+        H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Sget_simple_extent_dims second attribute failed");
+
+    /*----------------------------------------------------------------------
+    * check for comparable TYPE and SPACE
+    *----------------------------------------------------------------------
+    */
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_attr_data check for comparable TYPE and SPACE");
+
+    /* pass dims1 and dims2 for maxdims as well since attribute's maxdims
+    * are always same */
+    if(diff_can_type(ftype1_id, ftype2_id, rank1, rank2, dims1, dims2, dims1, dims2, name1, name2, opts, 0) == 1) {
+        /*-----------------------------------------------------------------
+        * "upgrade" the smaller memory size
+        *------------------------------------------------------------------
+        */
+        if(FAIL == match_up_memsize(ftype1_id, ftype2_id, &mtype1_id, &mtype2_id, &msize1, &msize2))
+            H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "match_up_memsize failed");
+
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_attr_data read");
+        /*---------------------------------------------------------------------
+        * read
+        *----------------------------------------------------------------------
+        */
+        nelmts1 = 1;
+        for(j = 0; j < rank1; j++)
+            nelmts1 *= dims1[j];
+
+        buf1 = (void *)HDcalloc((size_t)(nelmts1), msize1);
+        buf2 = (void *)HDcalloc((size_t)(nelmts1), msize2);
+        if(buf1 == NULL || buf2 == NULL) {
+            parallel_print("cannot read into memory\n");
+            H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "buffer allocation failed");
+        }
+        if(H5Aread(attr1_id, mtype1_id, buf1) < 0) {
+            parallel_print("Failed reading attribute1 %s\n", name1);
+            H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_type first attribute failed");
+        }
+        else
+            buf1hasdata = TRUE;
+
+        if(H5Aread(attr2_id, mtype2_id, buf2) < 0) {
+            parallel_print("Failed reading attribute2 %s\n", name2);
+            H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_type second attribute failed");
+        }
+        else
+            buf2hasdata = TRUE;
+
+        /* format output string */
+        HDsnprintf(np1, sizeof(np1), "%s of <%s>", name1, path1);
+        HDsnprintf(np2, sizeof(np1), "%s of <%s>", name2, path2);
+
+        /*---------------------------------------------------------------------
+        * array compare
+        *----------------------------------------------------------------------
+        */
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_attr_data array compare %s - %s", name1, name1);
+
+        /* always print name */
+        /* verbose (-v) and report (-r) mode */
+        if(opts->m_verbose || opts->m_report) {
+            do_print_attrname("attribute", np1, np2);
+
+            nfound = diff_array(buf1, buf2, nelmts1, (hsize_t) 0, rank1,
+                    dims1, opts, np1, np2, mtype1_id, attr1_id, attr2_id);
+            print_found(nfound);
+        }
+        /* quiet mode (-q), just count differences */
+        else if(opts->m_quiet) {
+            nfound = diff_array(buf1, buf2, nelmts1, (hsize_t) 0, rank1,
+                    dims1, opts, np1, np2, mtype1_id, attr1_id, attr2_id);
+        }
+        /* the rest (-c, none, ...) */
+        else {
+            nfound = diff_array(buf1, buf2, nelmts1, (hsize_t) 0, rank1,
+                    dims1, opts, np1, np2, mtype1_id, attr1_id, attr2_id);
+
+            /* print info if compatible and difference found */
+            if (nfound) {
+                do_print_attrname("attribute", np1, np2);
+                print_found(nfound);
+            } /* end if */
+        } /* end else */
+    }
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_attr_data check for comparable TYPE and SPACE complete nfound:%d - errstat:%d", nfound, opts->err_stat);
+
+    /*----------------------------------------------------------------------
+    * close
+    *----------------------------------------------------------------------
+    */
+
+    /* Free buf1 and buf2, check both VLEN-data VLEN-string to reclaim any
+    * VLEN memory first */
+    if(TRUE == h5tools_detect_vlen(mtype1_id))
+        H5Treclaim(mtype1_id, space1_id, H5P_DEFAULT, buf1);
+    HDfree(buf1);
+    buf1 = NULL;
+
+    if(TRUE == h5tools_detect_vlen(mtype2_id))
+        H5Treclaim(mtype2_id, space2_id, H5P_DEFAULT, buf2);
+    HDfree(buf2);
+    buf2 = NULL;
+
+    if(H5Tclose(ftype1_id) < 0)
+        H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_type first attribute failed");
+    if(H5Tclose(ftype2_id) < 0)
+        H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_type second attribute failed");
+    if(H5Sclose(space1_id) < 0)
+        H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_type first attribute failed");
+    if(H5Sclose(space2_id) < 0)
+        H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_type second attribute failed");
+    if(H5Tclose(mtype1_id) < 0)
+        H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tclose first attribute mtype failed");
+    if(H5Tclose(mtype2_id) < 0)
+        H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tclose second attribute mtype failed");
+
+done:
+    opts->err_stat = opts->err_stat | ret_value;
+
+    H5E_BEGIN_TRY {
+        if(buf1) {
+            if(buf1hasdata && TRUE == h5tools_detect_vlen(mtype1_id))
+                H5Treclaim(mtype1_id, space1_id, H5P_DEFAULT, buf1);
+            HDfree(buf1);
+        } /* end if */
+        if(buf2) {
+            if(buf2hasdata && TRUE == h5tools_detect_vlen(mtype2_id))
+                H5Treclaim(mtype2_id, space2_id, H5P_DEFAULT, buf2);
+            HDfree(buf2);
+        } /* end if */
+
+        H5Tclose(ftype1_id);
+        H5Tclose(ftype2_id);
+        H5Tclose(mtype1_id);
+        H5Tclose(mtype2_id);
+        H5Sclose(space1_id);
+        H5Sclose(space2_id);
+    } H5E_END_TRY;
+
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_attr_data end - errstat:%d", opts->err_stat);
+
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
+    return nfound;
+}
+
+/*-------------------------------------------------------------------------
+ * Function: diff_attr
+ *
+ * Purpose:  compare attributes located in LOC1_ID and LOC2_ID, which are
+ *           obtained either from
+ *               loc_id = H5Gopen2(fid, name, H5P_DEFAULT);
+ *               loc_id = H5Dopen2(fid, name);
+ *               loc_id = H5Topen2(fid, name, H5P_DEFAULT);
+ *
+ * Return:   number of differences found
+ *-------------------------------------------------------------------------
+ */
+
+hsize_t diff_attr(hid_t loc1_id, hid_t loc2_id, const char *path1, const char *path2, diff_opt_t *opts)
+{
+    H5TOOLS_ERR_INIT(int, opts->err_stat)
+    hid_t      attr1_id = H5I_INVALID_HID;     /* attr ID */
+    hid_t      attr2_id = H5I_INVALID_HID;     /* attr ID */
+    char       *name1 = NULL;
+    char       *name2 = NULL;
+    unsigned   u;                 /* Local index variable */
+    hsize_t    nfound = 0;
+    hsize_t    nfound_total = 0;
+
+    H5TOOLS_PUSH_STACK();
     table_attrs_t *match_list_attrs = NULL;
-    h5difftrace("diff_attr start\n");
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_attr start - errstat:%d", opts->err_stat);
 
     if(build_match_list_attrs(loc1_id, loc2_id, &match_list_attrs, opts) < 0) {
         H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "build_match_list_attrs failed");
     }
-    h5diffdebug2("build_match_list_attrs - errstat:%d\n", opts->err_stat);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "build_match_list_attrs - errstat:%d", opts->err_stat);
 
     /* if detect any unique extra attr */
     if(match_list_attrs->nattrs_only1 || match_list_attrs->nattrs_only2) {
-        h5difftrace("diff_attr attributes only in one file\n");
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_attr attributes only in one file");
         /* exit will be 1 */
         opts->contents = 0;
     }
-    h5diffdebug2("match_list_attrs info - errstat:%d\n", opts->err_stat);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g,"match_list_attrs info - errstat:%d", opts->err_stat);
 
     for(u = 0; u < (unsigned)match_list_attrs->nattrs; u++) {
-        h5diffdebug3("match_list_attrs loop[%d] - errstat:%d\n", u, opts->err_stat);
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "match_list_attrs loop[%d] - errstat:%d", u, opts->err_stat);
         if((match_list_attrs->attrs[u].exist[0]) && (match_list_attrs->attrs[u].exist[1])) {
             name1 = name2 = match_list_attrs->attrs[u].name;
-            h5diffdebug2("diff_attr name - %s\n", name1);
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_attr name - %s", name1);
 
             /*--------------
             * attribute 1 */
@@ -379,167 +584,12 @@ hsize_t diff_attr(hid_t loc1_id,
             if((attr2_id = H5Aopen(loc2_id, name2, H5P_DEFAULT)) < 0)
                 H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aopen second attribute failed");
 
-            h5difftrace("diff_attr got attributes\n");
-            /* get the datatypes  */
-            if((ftype1_id = H5Aget_type(attr1_id)) < 0)
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_type first attribute failed");
-            if((ftype2_id = H5Aget_type(attr2_id)) < 0)
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_type second attribute failed");
-
-            if((mtype1_id = H5Tget_native_type(ftype1_id, H5T_DIR_DEFAULT)) < 0)
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tget_native_type first attribute ftype failed");
-            if((mtype2_id = H5Tget_native_type(ftype2_id, H5T_DIR_DEFAULT)) < 0)
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tget_native_type second attribute ftype failed");
-            if((msize1 = H5Tget_size(mtype1_id)) == 0)
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tget_size first attribute mtype failed");
-            if((msize2 = H5Tget_size(mtype2_id)) == 0)
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tget_size second attribute mtype failed");
-
-            /* get the dataspace   */
-            if((space1_id = H5Aget_space(attr1_id)) < 0)
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_space first attribute failed");
-            if((space2_id = H5Aget_space(attr2_id)) < 0)
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_space second attribute failed");
-
-            /* get dimensions  */
-            if((rank1 = H5Sget_simple_extent_dims(space1_id, dims1, NULL)) < 0)
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Sget_simple_extent_dims first attribute failed");
-            if((rank2 = H5Sget_simple_extent_dims(space2_id, dims2, NULL)) < 0)
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Sget_simple_extent_dims second attribute failed");
-
-            /*----------------------------------------------------------------------
-            * check for comparable TYPE and SPACE
-            *----------------------------------------------------------------------
-            */
-
-            /* pass dims1 and dims2 for maxdims as well since attribute's maxdims
-            * are always same */
-            if(diff_can_type(ftype1_id, ftype2_id, rank1, rank2, dims1, dims2,
-                    dims1, dims2, name1, name2, opts, 0) != 1) {
-                if(H5Tclose(ftype1_id) < 0)
-                    H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tclose first attribute ftype failed");
-                if(H5Tclose(ftype2_id) < 0)
-                    H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tclose second attribute ftype failed");
-                if(H5Sclose(space1_id) < 0)
-                    H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Sclose first attribute failed");
-                if(H5Sclose(space2_id) < 0)
-                    H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Sclose second attribute failed");
-                if(H5Aclose(attr1_id) < 0)
-                    H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aclose first attribute failed");
-                if(H5Aclose(attr2_id) < 0)
-                    H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aclose second attribute failed");
-                if(H5Tclose(mtype1_id) < 0)
-                    H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tclose first attribute mtype failed");
-                if(H5Tclose(mtype2_id) < 0)
-                    H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tclose second attribute mtype failed");
-
-                continue;
-            }
-
-            /*-----------------------------------------------------------------
-            * "upgrade" the smaller memory size
-            *------------------------------------------------------------------
-            */
-            if(FAIL == match_up_memsize(ftype1_id, ftype2_id, &mtype1_id,
-                            &mtype2_id, &msize1, &msize2))
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "match_up_memsize failed");
-
-            /*---------------------------------------------------------------------
-            * read
-            *----------------------------------------------------------------------
-            */
-            nelmts1 = 1;
-            for(j = 0; j < rank1; j++)
-                nelmts1 *= dims1[j];
-
-            buf1 = (void *)HDcalloc((size_t)(nelmts1), msize1);
-            buf2 = (void *)HDcalloc((size_t)(nelmts1), msize2);
-            if(buf1 == NULL || buf2 == NULL) {
-                parallel_print("cannot read into memory\n");
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "buffer allocation failed");
-            }
-            if(H5Aread(attr1_id, mtype1_id, buf1) < 0) {
-                parallel_print("Failed reading attribute1 %s/%s\n", path1, name1);
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_type first attribute failed");
-            }
-            else
-                buf1hasdata = TRUE;
-
-            if(H5Aread(attr2_id, mtype2_id, buf2) < 0) {
-                parallel_print("Failed reading attribute2 %s/%s\n", path2, name2);
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_type second attribute failed");
-            }
-            else
-                buf2hasdata = TRUE;
-
-            /* format output string */
-            HDsnprintf(np1, sizeof(np1), "%s of <%s>", name1, path1);
-            HDsnprintf(np2, sizeof(np1), "%s of <%s>", name2, path2);
-
-            /*---------------------------------------------------------------------
-            * array compare
-            *----------------------------------------------------------------------
-            */
-
-            /* always print name */
-            /* verbose (-v) and report (-r) mode */
-            if(opts->m_verbose || opts->m_report) {
-                do_print_attrname("attribute", np1, np2);
-
-                nfound = diff_array(buf1, buf2, nelmts1, (hsize_t) 0, rank1,
-                        dims1, opts, np1, np2, mtype1_id, attr1_id, attr2_id);
-                print_found(nfound);
-            }
-            /* quiet mode (-q), just count differences */
-            else if(opts->m_quiet) {
-                nfound = diff_array(buf1, buf2, nelmts1, (hsize_t) 0, rank1,
-                        dims1, opts, np1, np2, mtype1_id, attr1_id, attr2_id);
-            }
-            /* the rest (-c, none, ...) */
-            else {
-                nfound = diff_array(buf1, buf2, nelmts1, (hsize_t) 0, rank1,
-                        dims1, opts, np1, np2, mtype1_id, attr1_id, attr2_id);
-
-                /* print info if compatible and difference found */
-                if (nfound) {
-                    do_print_attrname("attribute", np1, np2);
-                    print_found(nfound);
-                } /* end if */
-            } /* end else */
-
-            /*----------------------------------------------------------------------
-            * close
-            *----------------------------------------------------------------------
-            */
-
-            /* Free buf1 and buf2, check both VLEN-data VLEN-string to reclaim any
-            * VLEN memory first */
-            if(TRUE == h5tools_detect_vlen(mtype1_id))
-                H5Treclaim(mtype1_id, space1_id, H5P_DEFAULT, buf1);
-            HDfree(buf1);
-            buf1 = NULL;
-
-            if(TRUE == h5tools_detect_vlen(mtype2_id))
-                H5Treclaim(mtype2_id, space2_id, H5P_DEFAULT, buf2);
-            HDfree(buf2);
-            buf2 = NULL;
-
-            if(H5Tclose(ftype1_id) < 0)
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_type first attribute failed");
-            if(H5Tclose(ftype2_id) < 0)
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_type second attribute failed");
-            if(H5Sclose(space1_id) < 0)
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_type first attribute failed");
-            if(H5Sclose(space2_id) < 0)
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_type second attribute failed");
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_attr got attributes");
+            nfound = diff_attr_data(attr1_id, attr2_id, name1, name2, path1, path2, opts);
             if(H5Aclose(attr1_id) < 0)
                 H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_type first attribute failed");
             if(H5Aclose(attr2_id) < 0)
                 H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Aget_type second attribute failed");
-            if(H5Tclose(mtype1_id) < 0)
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tclose first attribute mtype failed");
-            if(H5Tclose(mtype2_id) < 0)
-                H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tclose second attribute mtype failed");
 
             nfound_total += nfound;
         }
@@ -549,30 +599,15 @@ done:
     opts->err_stat = opts->err_stat | ret_value;
 
     H5E_BEGIN_TRY {
-        if(buf1) {
-            if(buf1hasdata && TRUE == h5tools_detect_vlen(mtype1_id))
-                H5Treclaim(mtype1_id, space1_id, H5P_DEFAULT, buf1);
-            HDfree(buf1);
-        } /* end if */
-        if(buf2) {
-            if(buf2hasdata && TRUE == h5tools_detect_vlen(mtype2_id))
-                H5Treclaim(mtype2_id, space2_id, H5P_DEFAULT, buf2);
-            HDfree(buf2);
-        } /* end if */
-
         table_attrs_free(match_list_attrs);
 
-        H5Tclose(ftype1_id);
-        H5Tclose(ftype2_id);
-        H5Tclose(mtype1_id);
-        H5Tclose(mtype2_id);
-        H5Sclose(space1_id);
-        H5Sclose(space2_id);
         H5Aclose(attr1_id);
         H5Aclose(attr2_id);
     } H5E_END_TRY;
 
-    h5diffdebug2("diff_attr end - errstat:%d\n", opts->err_stat);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_attr end - errstat:%d", opts->err_stat);
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return nfound_total;
 }
 
diff --git a/tools/lib/h5diff_dset.c b/tools/lib/h5diff_dset.c
index 56c4f0b..5fb0ebf 100644
--- a/tools/lib/h5diff_dset.c
+++ b/tools/lib/h5diff_dset.c
@@ -33,7 +33,7 @@ hsize_t diff_dataset(hid_t file1_id,
                      const char *obj2_name,
                      diff_opt_t *opts)
 {
-    int     ret_value = opts->err_stat;
+    H5TOOLS_ERR_INIT(int, opts->err_stat)
     int     status = -1;
     hid_t   did1 = -1;
     hid_t   did2 = -1;
@@ -41,7 +41,8 @@ hsize_t diff_dataset(hid_t file1_id,
     hid_t   dcpl2 = -1;
     hsize_t nfound = 0;
 
-    h5difftrace("diff_dataset start\n");
+    H5TOOLS_PUSH_STACK();
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_dataset start - errstat:%d", opts->err_stat);
     /*-------------------------------------------------------------------------
      * open the handles
      *-------------------------------------------------------------------------
@@ -68,6 +69,7 @@ hsize_t diff_dataset(hid_t file1_id,
      * 2) the internal filters might be turned off
      *-------------------------------------------------------------------------
      */
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_dataset h5tools_canreadf then diff_datasetid");
     if ((status = h5tools_canreadf((opts->m_verbose ? obj1_name : NULL), dcpl1) == 1) &&
             (status = h5tools_canreadf((opts->m_verbose ? obj2_name : NULL), dcpl2) == 1))
         nfound = diff_datasetid(did1, did2, obj1_name, obj2_name, opts);
@@ -91,7 +93,9 @@ done:
         /* enable error reporting */
     } H5E_END_TRY;
 
-    h5diffdebug3("diff_dataset finish:%d - errstat:%d\n", nfound, opts->err_stat);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_dataset finish:%d - errstat:%d", nfound, opts->err_stat);
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return nfound;
 }
 
@@ -152,16 +156,16 @@ hsize_t diff_datasetid(hid_t did1,
                        const char *obj2_name,
                        diff_opt_t *opts)
 {
-    int        ret_value = opts->err_stat;
-    hid_t      sid1 = -1;
-    hid_t      sid2 = -1;
-    hid_t      f_tid1 = -1;
-    hid_t      f_tid2 = -1;
-    hid_t      dam_tid = -1;             /* m_tid for diff_array function */
-    hid_t      m_tid1 = -1;
-    hid_t      m_tid2 = -1;
-    hid_t      dcpl1 = -1;
-    hid_t      dcpl2 = -1;
+    H5TOOLS_ERR_INIT(int, opts->err_stat)
+    hid_t      sid1 = H5I_INVALID_HID;
+    hid_t      sid2 = H5I_INVALID_HID;
+    hid_t      f_tid1 = H5I_INVALID_HID;
+    hid_t      f_tid2 = H5I_INVALID_HID;
+    hid_t      dam_tid = H5I_INVALID_HID;             /* m_tid for diff_array function */
+    hid_t      m_tid1 = H5I_INVALID_HID;
+    hid_t      m_tid2 = H5I_INVALID_HID;
+    hid_t      dcpl1 = H5I_INVALID_HID;
+    hid_t      dcpl2 = H5I_INVALID_HID;
     H5D_layout_t     stl1 = -1;
     H5D_layout_t     stl2 = -1;
     size_t     dam_size;                /* m_size for diff_array function */
@@ -189,13 +193,14 @@ hsize_t diff_datasetid(hid_t did1,
     void       *buf2 = NULL;
     void       *sm_buf1 = NULL;
     void       *sm_buf2 = NULL;
-    hid_t      sm_space = -1;           /*stripmine data space */
+    hid_t      sm_space = H5I_INVALID_HID;           /*stripmine data space */
     size_t     need;                    /* bytes needed for malloc */
     int        i;
     unsigned int  vl_data1 = 0;          /*contains VL datatypes */
     unsigned int  vl_data2 = 0;          /*contains VL datatypes */
 
-    h5difftrace("diff_datasetid start\n");
+    H5TOOLS_PUSH_STACK();
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datasetid start - errstat:%d", opts->err_stat);
     /* Get the dataspace handle */
     if((sid1 = H5Dget_space(did1)) < 0)
         H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Dget_space failed");
@@ -219,7 +224,7 @@ hsize_t diff_datasetid(hid_t did1,
     /* Get dimensions */
     if(H5Sget_simple_extent_dims(sid2, dims2, maxdim2) < 0)
         H5TOOLS_GOTO_ERROR(FAIL, H5E_tools_min_id_g, "H5Sget_simple_extent_dims failed");
-    h5diffdebug3("rank: %ld - %ld\n", rank1, rank2);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "rank: %ld - %ld", rank1, rank2);
 
     /*-------------------------------------------------------------------------
      * get the file data type
@@ -252,11 +257,11 @@ hsize_t diff_datasetid(hid_t did1,
      * check for empty datasets
      *-------------------------------------------------------------------------
      */
-    h5difftrace("check for empty datasets\n");
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "check for empty datasets");
 
     storage_size1 = H5Dget_storage_size(did1);
     storage_size2 = H5Dget_storage_size(did2);
-    h5diffdebug3("storage size: %ld - %ld\n", storage_size1, storage_size2);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "storage size: %ld - %ld", storage_size1, storage_size2);
 
     if(storage_size1 == 0 || storage_size2 == 0) {
         if(stl1 == H5D_VIRTUAL || stl2 == H5D_VIRTUAL) {
@@ -280,33 +285,45 @@ hsize_t diff_datasetid(hid_t did1,
             obj1_name, obj2_name,
             opts, 0) != 1)
         can_compare = 0;
-    h5diffdebug2("diff_can_type - errstat:%d\n", opts->err_stat);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_can_type - errstat:%d", opts->err_stat);
 
     /*-------------------------------------------------------------------------
      * memory type and sizes
      *-------------------------------------------------------------------------
      */
-    h5difftrace("check for memory type and sizes\n");
-    if((m_tid1 = H5Tget_native_type(f_tid1, H5T_DIR_DEFAULT)) < 0)
-        H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tget_native_type failed");
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "check for memory type and sizes");
+    if (H5Tget_class(f_tid1) == H5T_REFERENCE) {
+        if((m_tid1 = H5Tcopy(H5T_STD_REF)) < 0)
+            H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tcopy(H5T_STD_REF) first ftype failed");
+    }
+    else {
+        if((m_tid1 = H5Tget_native_type(f_tid1, H5T_DIR_DEFAULT)) < 0)
+            H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tget_native_type first ftype failed");
+    }
 
-    if((m_tid2 = H5Tget_native_type(f_tid2, H5T_DIR_DEFAULT)) < 0)
-        H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tget_native_type failed");
+    if (H5Tget_class(f_tid2) == H5T_REFERENCE) {
+        if((m_tid2 = H5Tcopy(H5T_STD_REF)) < 0)
+            H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tcopy(H5T_STD_REF) second ftype failed");
+    }
+    else {
+        if((m_tid2 = H5Tget_native_type(f_tid2, H5T_DIR_DEFAULT)) < 0)
+            H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Tget_native_type second ftype failed");
+    }
 
     m_size1 = H5Tget_size(m_tid1);
     m_size2 = H5Tget_size(m_tid2);
-    h5diffdebug3("type size: %ld - %ld\n", m_size1, m_size2);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "type size: %ld - %ld", m_size1, m_size2);
 
     /*-------------------------------------------------------------------------
      * check for different signed/unsigned types
      *-------------------------------------------------------------------------
      */
     if(can_compare) {
-        h5difftrace("can_compare for sign\n");
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "can_compare for sign");
         sign1 = H5Tget_sign(m_tid1);
         sign2 = H5Tget_sign(m_tid2);
         if(sign1 != sign2) {
-            h5difftrace("sign1 != sign2\n");
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "sign1 != sign2");
             if((opts->m_verbose || opts->m_list_not_cmp) && obj1_name && obj2_name) {
                 parallel_print("Not comparable: <%s> has sign %s ", obj1_name, get_sign(sign1));
                 parallel_print("and <%s> has sign %s\n", obj2_name, get_sign(sign2));
@@ -315,6 +332,7 @@ hsize_t diff_datasetid(hid_t did1,
             can_compare = 0;
             opts->not_cmp = 1;
         }
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "can_compare for sign - can_compare=%d opts->not_cmp=%d", can_compare, opts->not_cmp);
     }
 
     /* Check if type is either VLEN-data or VLEN-string to reclaim any
@@ -324,7 +342,7 @@ hsize_t diff_datasetid(hid_t did1,
         vl_data1 = TRUE;
     if(TRUE == h5tools_detect_vlen(m_tid2))
         vl_data2 = TRUE;
-    h5diffdebug2("h5tools_detect_vlen - errstat:%d\n", opts->err_stat);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "h5tools_detect_vlen %d:%d - errstat:%d", vl_data1, vl_data2, opts->err_stat);
 
     /*------------------------------------------------------------------------
      * only attempt to compare if possible
@@ -332,7 +350,7 @@ hsize_t diff_datasetid(hid_t did1,
      */
     if(can_compare) { /* it is possible to compare */
         H5T_class_t  tclass = H5Tget_class(f_tid1);
-        h5difftrace("can_compare attempt\n");
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "can_compare attempt");
 
         /*-----------------------------------------------------------------
         * get number of elements
@@ -346,19 +364,19 @@ hsize_t diff_datasetid(hid_t did1,
         for(i = 0; i < rank2; i++)
             nelmts2 *= dims2[i];
 
-        h5diffdebug3("nelmts: %ld - %ld\n", nelmts1, nelmts2);
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "nelmts: %ld - %ld", nelmts1, nelmts2);
 
         if(tclass != H5T_ARRAY) {
             /*-----------------------------------------------------------------
              * "upgrade" the smaller memory size
              *------------------------------------------------------------------
              */
-            h5difftrace("upgrade the smaller memory size?\n");
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "NOT H5T_ARRAY, upgrade the smaller memory size?");
             if (FAIL == match_up_memsize (f_tid1, f_tid2,
                                         &m_tid1, &m_tid2,
                                         &m_size1, &m_size2))
                 H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "match_up_memsize failed");
-            h5diffdebug3("m_size: %ld - %ld\n", m_size1, m_size2);
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "m_size: %ld - %ld", m_size1, m_size2);
             dadims = dims1;
             dam_size = m_size1;
             dam_tid = m_tid1;
@@ -366,7 +384,7 @@ hsize_t diff_datasetid(hid_t did1,
             need = (size_t)(nelmts1 * m_size1);  /* bytes needed */
         }
         else {
-            h5diffdebug3("Array dims: %d - %d\n", dims1[0], dims2[0]);
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "Array dims: %d - %d", dims1[0], dims2[0]);
             /* Compare the smallest array, but create the largest buffer */
             if(m_size1 <= m_size2) {
                 dadims = dims1;
@@ -388,9 +406,10 @@ hsize_t diff_datasetid(hid_t did1,
             name1 = diff_basename(obj1_name);
         if(obj2_name)
             name2 = diff_basename(obj2_name);
-        h5diffdebug3("obj_names: %s - %s\n", name1, name2);
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "obj_names: %s - %s", name1, name2);
 
 
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "read/compare");
         /*----------------------------------------------------------------
          * read/compare
          *-----------------------------------------------------------------
@@ -401,23 +420,24 @@ hsize_t diff_datasetid(hid_t did1,
         } /* end if */
 
         if(buf1 != NULL && buf2 != NULL) {
-            h5difftrace("buf1 != NULL && buf2 != NULL\n");
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "buf1 != NULL && buf2 != NULL");
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "H5Dread did1");
             if(H5Dread(did1, m_tid1, H5S_ALL, H5S_ALL, H5P_DEFAULT, buf1) < 0)
                 H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Dread failed");
-            h5difftrace("H5Dread did2\n");
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "H5Dread did2");
             if(H5Dread(did2, m_tid2, H5S_ALL, H5S_ALL, H5P_DEFAULT, buf2) < 0)
                 H5TOOLS_GOTO_ERROR(1, H5E_tools_min_id_g, "H5Dread failed");
 
             /* array diff */
             nfound = diff_array(buf1, buf2, danelmts, (hsize_t)0, rank1, dadims,
                 opts, name1, name2, dam_tid, did1, did2);
-            h5diffdebug2("diff_array nfound:%d\n", nfound);
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_array nfound:%d - errstat:%d", nfound, opts->err_stat);
 
             /* reclaim any VL memory, if necessary */
-            h5diffdebug2("check vl_data1:%d\n", vl_data1);
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "check vl_data1:%d", vl_data1);
             if(vl_data1)
                 H5Treclaim(m_tid1, sid1, H5P_DEFAULT, buf1);
-            h5diffdebug2("check vl_data2:%d\n", vl_data2);
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "check vl_data2:%d", vl_data2);
             if(vl_data2)
                 H5Treclaim(m_tid2, sid2, H5P_DEFAULT, buf2);
             if(buf1 != NULL) {
@@ -459,7 +479,7 @@ hsize_t diff_datasetid(hid_t did1,
                     size = 1;
                 sm_size[i - 1] = MIN(dadims[i - 1], size);
                 sm_nbytes *= sm_size[i - 1];
-                h5diffdebug2("sm_nbytes: %ld\n", sm_nbytes);
+                H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "sm_nbytes: %ld", sm_nbytes);
             } /* end for */
 
             /* malloc return code should be verified.
@@ -534,6 +554,7 @@ hsize_t diff_datasetid(hid_t did1,
 
             H5Sclose(sm_space);
         } /* hyperslab read */
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "can_compare complete");
     } /*can_compare*/
 
 
@@ -541,7 +562,7 @@ hsize_t diff_datasetid(hid_t did1,
      * close
      *-------------------------------------------------------------------------
      */
-    h5diffdebug2("reclaim any VL memory - errstat:%d\n", opts->err_stat);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "reclaim any VL memory - errstat:%d", opts->err_stat);
 
 done:
     opts->err_stat = opts->err_stat | ret_value;
@@ -588,7 +609,9 @@ done:
         /* enable error reporting */
     } H5E_END_TRY;
 
-    h5diffdebug3("diff_datasetid return:%d with nfound:%d\n", ret_value, nfound);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_datasetid return:%d with nfound:%d", ret_value, nfound);
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return nfound;
 }
 
@@ -617,14 +640,15 @@ int diff_can_type(hid_t       f_tid1, /* file data type */
                   diff_opt_t  *opts,
                   int         is_compound)
 {
-    int          ret_value = 1;            /* can_compare value */
+    H5TOOLS_ERR_INIT(int, 1)               /* can_compare value */
     H5T_class_t  tclass1;
     H5T_class_t  tclass2;
     int          maxdim_diff = 0;          /* maximum dimensions are different */
     int          dim_diff = 0;             /* current dimensions are different */
     int          i;
 
-    h5difftrace("diff_can_type start\n");
+    H5TOOLS_PUSH_STACK();
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_can_type start");
     /*-------------------------------------------------------------------------
      * check for the same class
      *-------------------------------------------------------------------------
@@ -677,7 +701,7 @@ int diff_can_type(hid_t       f_tid1, /* file data type */
         case H5T_NO_CLASS:
         case H5T_NCLASSES:
         default:
-            h5diffdebug2("diff_can_type class - %s\n", get_class(tclass1));
+            H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_can_type class - %s", get_class(tclass1));
             break;
     } /* end switch */
 
@@ -775,7 +799,7 @@ int diff_can_type(hid_t       f_tid1, /* file data type */
     if(tclass1 == H5T_STRING) {
         htri_t vstrtype1 = -1;
         htri_t vstrtype2 = -1;
-        h5difftrace("diff_can_type end - H5T_STRING\n");
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_can_type end - H5T_STRING");
 
         vstrtype1 = H5Tis_variable_str(f_tid1);
         vstrtype2 = H5Tis_variable_str(f_tid2);
@@ -796,7 +820,7 @@ int diff_can_type(hid_t       f_tid1, /* file data type */
         int   j;
         hid_t memb_type1 = -1;
         hid_t memb_type2 = -1;
-        h5difftrace("diff_can_type end - H5T_COMPOUND\n");
+        H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_can_type end - H5T_COMPOUND");
 
         nmembs1 = H5Tget_nmembers(f_tid1);
         nmembs2 = H5Tget_nmembers(f_tid2);
@@ -831,7 +855,9 @@ done:
     if (ret_value < 0)
         opts->err_stat = 1;
 
-    h5diffdebug2("diff_can_type end - %d\n", ret_value);
+    H5TOOLS_DEBUG(H5E_tools_min_dbg_id_g, "diff_can_type end - %d", ret_value);
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return ret_value;
 }
 
diff --git a/tools/lib/h5diff_util.c b/tools/lib/h5diff_util.c
index 6b5ca2f..b54ffe1 100644
--- a/tools/lib/h5diff_util.c
+++ b/tools/lib/h5diff_util.c
@@ -339,8 +339,9 @@ herr_t match_up_memsize (hid_t f_tid1_id, hid_t f_tid2_id,
                          hid_t *m_tid1, hid_t *m_tid2,
                          size_t *m_size1, size_t  *m_size2)
 {
-    herr_t ret_value = SUCCEED;
+    H5TOOLS_ERR_INIT(herr_t, SUCCEED)
 
+    H5TOOLS_PUSH_STACK();
     if((*m_size1) != (*m_size2)) {
         if((*m_size1) < (*m_size2)) {
             H5Tclose(*m_tid1);
@@ -363,6 +364,8 @@ herr_t match_up_memsize (hid_t f_tid1_id, hid_t f_tid2_id,
         H5TOOLS_GOTO_ERROR(FAIL, H5E_tools_min_id_g, "native type sizes do not compare");
 
 done:
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return ret_value;
 }
 
diff --git a/tools/lib/h5tools.c b/tools/lib/h5tools.c
index 727e493..f70ecd2 100644
--- a/tools/lib/h5tools.c
+++ b/tools/lib/h5tools.c
@@ -436,8 +436,8 @@ h5tools_set_error_file(const char *fname, int is_bin)
 static hid_t
 h5tools_get_fapl(hid_t fapl, const char *driver, unsigned *drivernum)
 {
+    H5TOOLS_ERR_INIT(int, SUCCEED)
     hid_t       new_fapl = -1; /* Copy of file access property list passed in, or new property list */
-    int         ret_value = SUCCEED;
 
     /* Make a copy of the FAPL, for the file open call to use, eventually */
     if (fapl == H5P_DEFAULT) {
@@ -1534,6 +1534,7 @@ render_bin_output_region_data_blocks(hid_t region_id, FILE *stream,
     hsize_t      blkndx;
     hid_t        sid1 = -1;
 
+    H5TOOLS_PUSH_STACK();
     /* Get the dataspace of the dataset */
     if((sid1 = H5Dget_space(region_id)) < 0)
         H5TOOLS_THROW(FAIL, H5E_tools_min_id_g, "H5Dget_space failed");
@@ -1600,6 +1601,8 @@ CATCH
     if(H5Sclose(sid1) < 0)
         H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Sclose failed");
 
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return ret_value;
 }
 
@@ -1627,6 +1630,7 @@ render_bin_output_region_blocks(hid_t region_space, hid_t region_id,
     hid_t        dtype = -1;
     hid_t        type_id = -1;
 
+    H5TOOLS_PUSH_STACK();
     if((snblocks = H5Sget_select_hyper_nblocks(region_space)) <= 0)
         H5TOOLS_THROW(FALSE, H5E_tools_min_id_g, "H5Sget_select_hyper_nblocks failed");
     nblocks = (hsize_t)snblocks;
@@ -1650,7 +1654,7 @@ render_bin_output_region_blocks(hid_t region_space, hid_t region_id,
 
     render_bin_output_region_data_blocks(region_id, stream, container, ndims, type_id, nblocks, ptdata);
 
- done:
+done:
     HDfree(ptdata);
 
     if(type_id > 0 && H5Tclose(type_id) < 0)
@@ -1661,7 +1665,9 @@ render_bin_output_region_blocks(hid_t region_space, hid_t region_id,
 
     H5_LEAVE(TRUE)
 
- CATCH
+CATCH
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return ret_value;
 }
 
@@ -1693,6 +1699,7 @@ render_bin_output_region_data_points(hid_t region_space, hid_t region_id,
     hid_t    mem_space = -1;
     void    *region_buf = NULL;
 
+    H5TOOLS_PUSH_STACK();
     if((type_size = H5Tget_size(type_id)) == 0)
         H5TOOLS_GOTO_ERROR(FAIL, H5E_tools_min_id_g, "H5Tget_size failed");
 
@@ -1715,13 +1722,15 @@ render_bin_output_region_data_points(hid_t region_space, hid_t region_id,
     if(render_bin_output(stream, container, type_id, (char*)region_buf, npoints) < 0)
         H5TOOLS_GOTO_ERROR(FAIL, H5E_tools_min_id_g, "render_bin_output of data points failed");
 
- done:
+done:
     HDfree(region_buf);
     HDfree(dims1);
 
     if(H5Sclose(mem_space) < 0)
         H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Sclose failed");
 
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return ret_value;
 }
 
@@ -1747,6 +1756,7 @@ render_bin_output_region_points(hid_t region_space, hid_t region_id,
     hid_t    dtype = -1;
     hid_t    type_id = -1;
 
+    H5TOOLS_PUSH_STACK();
     if((snpoints = H5Sget_select_elem_npoints(region_space)) <= 0)
         H5TOOLS_THROW(FALSE, H5E_tools_min_id_g, "H5Sget_select_elem_npoints failed");
     npoints = (hsize_t)snpoints;
@@ -1764,7 +1774,7 @@ render_bin_output_region_points(hid_t region_space, hid_t region_id,
 
     render_bin_output_region_data_points(region_space, region_id, stream, container, ndims, type_id, npoints);
 
- done:
+done:
     if(type_id > 0 && H5Tclose(type_id) < 0)
         H5TOOLS_ERROR(H5E_tools_g, H5E_tools_min_id_g, "H5Tclose failed");
 
@@ -1773,6 +1783,8 @@ render_bin_output_region_points(hid_t region_space, hid_t region_id,
 
     H5_LEAVE(ret_value)
 CATCH
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return ret_value;
 }
 
diff --git a/tools/lib/h5tools_dump.c b/tools/lib/h5tools_dump.c
index 8b08d7f..55d3a6b 100644
--- a/tools/lib/h5tools_dump.c
+++ b/tools/lib/h5tools_dump.c
@@ -628,7 +628,7 @@ h5tools_print_region_data_blocks(hid_t region_id,
 
     } /* end for (blkndx = 0; blkndx < nblocks; blkndx++) */
 
- done:
+done:
     HDfree(start);
     HDfree(count);
     HDfree(region_buf);
@@ -1280,6 +1280,7 @@ h5tools_print_simple_subset(FILE *stream, const h5tool_format_t *info, h5tools_c
     /* VL data special information */
     unsigned int        vl_data = 0; /* contains VL datatypes */
 
+    H5TOOLS_PUSH_STACK();
     if ((size_t) ctx->ndims > NELMTS(sm_size))
         H5TOOLS_THROW(FAIL, H5E_tools_min_id_g, "ndims and sm_size comparision failed");
 
@@ -1400,6 +1401,8 @@ CATCH
     if(sm_buf)
         HDfree(sm_buf);
 
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return ret_value;
 }
 
@@ -1585,6 +1588,7 @@ h5tools_dump_simple_subset(FILE *stream, const h5tool_format_t *info, h5tools_co
     size_t            i;                       /* counters  */
     hsize_t           total_size[H5S_MAX_RANK];/* total size of dataset*/
 
+    H5TOOLS_PUSH_STACK();
     if((f_space = H5Dget_space(dset)) < 0)
         H5TOOLS_THROW(FAIL, H5E_tools_min_id_g, "H5Dget_space failed");
 
@@ -1610,6 +1614,8 @@ CATCH
     if(f_space >= 0 && H5Sclose(f_space) < 0)
         H5TOOLS_THROW(FAIL, H5E_tools_min_id_g, "H5Sclose failed");
 
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return ret_value;
 }
 
@@ -1979,6 +1985,8 @@ done:
     if (f_space > 0)
         H5Sclose(f_space);
 
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return ret_value;
 }
 
@@ -2002,6 +2010,7 @@ h5tools_dump_mem(FILE *stream, const h5tool_format_t *info, h5tools_context_t *c
     hid_t     f_type = H5I_INVALID_HID;
     h5tool_format_t    info_dflt;
 
+    H5TOOLS_PUSH_STACK();
     /* Use default values */
     if (!stream)
         stream = rawoutstream;
@@ -2047,6 +2056,8 @@ done:
     if (f_space > 0)
         H5Sclose(f_space);
 
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return ret_value;
 }
 
@@ -2088,6 +2099,7 @@ h5tools_print_datatype(FILE *stream, h5tools_str_t *buffer, const h5tool_format_
     const char  *sign_s = NULL;  /* sign scheme string */
     const char  *order_s = NULL; /* byte order string */
 
+    H5TOOLS_PUSH_STACK();
     if((type_class = H5Tget_class(type)) < 0)
         H5TOOLS_THROW(FAIL, H5E_tools_min_id_g, "H5Tget_class failed");
     if (object_search && H5Tcommitted(type) > 0) {
@@ -2633,6 +2645,8 @@ h5tools_print_datatype(FILE *stream, h5tools_str_t *buffer, const h5tool_format_
     }
 
 CATCH
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return ret_value;
 }
 
@@ -2657,6 +2671,7 @@ h5tools_print_dataspace(h5tools_str_t *buffer, hid_t space)
     H5S_class_t space_type = -1;
     int         i;
 
+    H5TOOLS_PUSH_STACK();
     if((ndims = H5Sget_simple_extent_dims(space, size, maxsize)) < 0)
         H5TOOLS_THROW(FAIL, H5E_tools_min_id_g, "H5Sget_simple_extent_dims failed");
 
@@ -2708,6 +2723,8 @@ h5tools_print_dataspace(h5tools_str_t *buffer, hid_t space)
     } /* end switch */
 
 CATCH
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return ret_value;
 }
 
@@ -2741,6 +2758,7 @@ h5tools_print_enum(FILE *stream, h5tools_str_t *buffer, const h5tool_format_t *i
     size_t         ncols = 80; /*available output width */
     hsize_t        curr_pos = 0;        /* total data element position   */
 
+    H5TOOLS_PUSH_STACK();
     if (info->line_ncols > 0)
         ncols = info->line_ncols;
 
@@ -2852,6 +2870,8 @@ CATCH
     if(0 == nmembs)
         h5tools_str_append(buffer, "\n<empty>");
 
+    H5TOOLS_ENDDEBUG(H5E_tools_min_dbg_id_g, "exit");
+    H5TOOLS_POP_STACK();
     return ret_value;
 }
 
diff --git a/tools/lib/h5tools_error.h b/tools/lib/h5tools_error.h
index 2c5e6c9..6e20b7c 100644
--- a/tools/lib/h5tools_error.h
+++ b/tools/lib/h5tools_error.h
@@ -112,7 +112,7 @@ H5TOOLS_DLLVAR hid_t H5E_tools_min_dbg_id_g;
  * H5TOOLS_INFO macro, used to facilitate error reporting .  The arguments are the minor error number, and a description of the error.
  */
 #define H5TOOLS_INFO(min_id, ...) {                                                                        \
-        H5Epush2(H5tools_ERR_STACK_g, __FILE__, FUNC, __LINE__, H5tools_ERR_CLS_g, H5E_tools_g, min_id, __VA_ARGS__);     \
+        H5Epush2(estack_id, __FILE__, FUNC, __LINE__, H5tools_ERR_CLS_g, H5E_tools_g, min_id, __VA_ARGS__);     \
 }
 
 /*
@@ -120,7 +120,7 @@ H5TOOLS_DLLVAR hid_t H5E_tools_min_dbg_id_g;
  * error number, the minor error number, and a description of the error.
  */
 #define H5TOOLS_ERROR(maj_id, min_id, ...) {                                                                        \
-        H5Epush2(H5tools_ERR_STACK_g, __FILE__, FUNC, __LINE__, H5tools_ERR_CLS_g, maj_id, min_id, __VA_ARGS__);     \
+        H5Epush2(estack_id, __FILE__, FUNC, __LINE__, H5tools_ERR_CLS_g, maj_id, min_id, __VA_ARGS__);     \
         ret_value = FAIL;                                                                                    \
 }
 
@@ -152,7 +152,7 @@ H5TOOLS_DLLVAR hid_t H5E_tools_min_dbg_id_g;
  * to the `catch_except' label, if we're not already past it.
  */
 #define H5TOOLS_THROW(fail_value, min_id, ...) {        \
-    H5Epush2(H5tools_ERR_STACK_g, __FILE__, FUNC, __LINE__, H5tools_ERR_CLS_g, H5E_tools_g, min_id, __VA_ARGS__);     \
+    H5Epush2(estack_id, __FILE__, FUNC, __LINE__, H5tools_ERR_CLS_g, H5E_tools_g, min_id, __VA_ARGS__);     \
     H5_LEAVE(fail_value)                               \
 }
 
diff --git a/tools/lib/h5tools_filters.c b/tools/lib/h5tools_filters.c
index aafc7ba..acaf24a 100644
--- a/tools/lib/h5tools_filters.c
+++ b/tools/lib/h5tools_filters.c
@@ -43,7 +43,7 @@ int
 h5tools_canreadf(const char* name,     /* object name, serves also as boolean print */
                      hid_t dcpl_id)    /* dataset creation property list */
 {
-    int ret_value = 1;
+    H5TOOLS_ERR_INIT(int, 1)
     int nfilters;       /* number of filters */
     H5Z_filter_t filtn; /* filter identification number */
     int i;              /* index */
@@ -144,7 +144,7 @@ done:
 H5_ATTR_CONST int
 h5tools_can_encode(H5Z_filter_t filtn)
 {
-    int ret_value = 1;
+    H5TOOLS_ERR_INIT(int, 1)
 
     switch (filtn) {
     /* user defined filter     */
diff --git a/tools/lib/h5tools_utils.c b/tools/lib/h5tools_utils.c
index 7b47f4d..96f1e04 100644
--- a/tools/lib/h5tools_utils.c
+++ b/tools/lib/h5tools_utils.c
@@ -788,7 +788,7 @@ herr_t
 init_objs(hid_t fid, find_objs_t *info, table_t **group_table,
     table_t **dset_table, table_t **type_table)
 {
-    herr_t ret_value = SUCCEED;
+    H5TOOLS_ERR_INIT(herr_t, SUCCEED)
 
     /* Initialize the tables */
     init_table(group_table);
@@ -1047,9 +1047,9 @@ h5tools_getstatus(void)
 int
 h5tools_getenv_update_hyperslab_bufsize(void)
 {
+    H5TOOLS_ERR_INIT(int, 1)
     const char *env_str = NULL;
     long hyperslab_bufsize_mb;
-    int ret_value = 1;
 
     /* check if environment variable is set for the hyperslab buffer size */
     if (NULL != (env_str = HDgetenv ("H5TOOLS_BUFSIZE"))) {
diff --git a/tools/lib/h5trav.c b/tools/lib/h5trav.c
index 4f4f42a..ab1635c 100644
--- a/tools/lib/h5trav.c
+++ b/tools/lib/h5trav.c
@@ -114,7 +114,7 @@ h5trav_set_verbose(int print_verbose)
  *-------------------------------------------------------------------------
  */
 
-
+
 /*-------------------------------------------------------------------------
  * Function: trav_addr_add
  *
@@ -140,7 +140,7 @@ trav_addr_add(trav_addr_t *visited, haddr_t addr, const char *path)
     visited->objs[idx].path = HDstrdup(path);
 } /* end trav_addr_add() */
 
-
+
 /*-------------------------------------------------------------------------
  * Function: trav_addr_visited
  *
@@ -164,7 +164,7 @@ trav_addr_visited(trav_addr_t *visited, haddr_t addr)
     return(NULL);
 } /* end trav_addr_visited() */
 
-
+
 /*-------------------------------------------------------------------------
  * Function: traverse_cb
  *
@@ -239,7 +239,7 @@ traverse_cb(hid_t loc_id, const char *path, const H5L_info_t *linfo,
     return(H5_ITER_CONT);
 } /* end traverse_cb() */
 
-
+
 /*-------------------------------------------------------------------------
  * Function: traverse
  *
@@ -254,8 +254,8 @@ static int
 traverse(hid_t file_id, const char *grp_name, hbool_t visit_start,
         hbool_t recurse, const trav_visitor_t *visitor, unsigned fields)
 {
+    H5TOOLS_ERR_INIT(int, SUCCEED)
     H5O_info_t  oinfo;          /* Object info for starting group */
-    int         ret_value = SUCCEED;
 
     /* Get info for starting object */
     if(H5Oget_info_by_name2(file_id, grp_name, &oinfo, fields, H5P_DEFAULT) < 0)
@@ -312,7 +312,7 @@ done:
     return ret_value;
 }
 
-
+
 /*-------------------------------------------------------------------------
  * Function: trav_info_add
  *
@@ -366,7 +366,7 @@ trav_fileinfo_add(trav_info_t *info, hid_t loc_id)
     info->paths[idx].fileno = oinfo.fileno;
 } /* end trav_fileinfo_add() */
 
-
+
 /*-------------------------------------------------------------------------
  * Function: trav_info_visit_obj
  *
@@ -396,7 +396,7 @@ trav_info_visit_obj(const char *path, const H5O_info_t *oinfo,
     return(0);
 } /* end trav_info_visit_obj() */
 
-
+
 /*-------------------------------------------------------------------------
  * Function: trav_info_visit_lnk
  *
@@ -415,7 +415,7 @@ trav_info_visit_lnk(const char *path, const H5L_info_t *linfo, void *udata)
     return(0);
 } /* end trav_info_visit_lnk() */
 
-
+
 /*-------------------------------------------------------------------------
  * Function: h5trav_getinfo
  *
@@ -429,8 +429,8 @@ trav_info_visit_lnk(const char *path, const H5L_info_t *linfo, void *udata)
 int
 h5trav_getinfo(hid_t file_id, trav_info_t *info)
 {
+    H5TOOLS_ERR_INIT(int, SUCCEED)
     trav_visitor_t info_visitor;        /* Visitor structure for trav_info_t's */
-    int            ret_value = SUCCEED;
 
     /* Init visitor structure */
     info_visitor.visit_obj = trav_info_visit_obj;
@@ -501,7 +501,7 @@ trav_info_init(const char *filename, hid_t fileid, trav_info_t **_info)
     *_info = info;
 } /* end trav_info_init() */
 
-
+
 /*-------------------------------------------------------------------------
  * Function: trav_info_free
  *
@@ -536,7 +536,7 @@ trav_info_free(trav_info_t *info)
  *-------------------------------------------------------------------------
  */
 
-
+
 /*-------------------------------------------------------------------------
  * Function: trav_table_visit_obj
  *
@@ -563,7 +563,7 @@ trav_table_visit_obj(const char *path, const H5O_info_t *oinfo,
     return 0;
 } /* end trav_table_visit_obj() */
 
-
+
 /*-------------------------------------------------------------------------
  * Function: trav_table_visit_lnk
  *
@@ -582,7 +582,7 @@ trav_table_visit_lnk(const char *path, const H5L_info_t H5_ATTR_UNUSED *linfo, v
     return 0;
 } /* end trav_table_visit_lnk() */
 
-
+
 /*-------------------------------------------------------------------------
  * Function: h5trav_gettable
  *
@@ -595,8 +595,8 @@ trav_table_visit_lnk(const char *path, const H5L_info_t H5_ATTR_UNUSED *linfo, v
 int
 h5trav_gettable(hid_t fid, trav_table_t *table)
 {
+    H5TOOLS_ERR_INIT(int, SUCCEED)
     trav_visitor_t table_visitor;       /* Visitor structure for trav_table_t's */
-    int            ret_value = SUCCEED;
 
     /* Init visitor structure */
     table_visitor.visit_obj = trav_table_visit_obj;
@@ -882,7 +882,7 @@ trav_attr(hid_t
     return(0);
 }
 
-
+
 /*-------------------------------------------------------------------------
  * Function: trav_print_visit_obj
  *
@@ -940,7 +940,7 @@ trav_print_visit_obj(const char *path, const H5O_info_t *oinfo,
     return(0);
 } /* end trav_print_visit_obj() */
 
-
+
 /*-------------------------------------------------------------------------
  * Function: trav_print_visit_lnk
  *
@@ -1004,7 +1004,7 @@ trav_print_visit_lnk(const char *path, const H5L_info_t *linfo, void *udata)
     return(0);
 } /* end trav_print_visit_lnk() */
 
-
+
 /*-------------------------------------------------------------------------
  * Function: h5trav_print
  *
@@ -1017,9 +1017,9 @@ trav_print_visit_lnk(const char *path, const H5L_info_t *linfo, void *udata)
 int
 h5trav_print(hid_t fid)
 {
+    H5TOOLS_ERR_INIT(int, SUCCEED)
     trav_print_udata_t print_udata;     /* User data for traversal */
     trav_visitor_t print_visitor;       /* Visitor structure for printing objects */
-    int            ret_value = SUCCEED;
 
     /* Init user data for printing */
     print_udata.fid = fid;
@@ -1037,7 +1037,7 @@ done:
     return ret_value;
 }
 
-
+
 /*-------------------------------------------------------------------------
  * Function: h5trav_visit
  *
@@ -1052,8 +1052,8 @@ h5trav_visit(hid_t fid, const char *grp_name, hbool_t visit_start,
     hbool_t recurse, h5trav_obj_func_t visit_obj, h5trav_lnk_func_t visit_lnk,
     void *udata, unsigned fields)
 {
+    H5TOOLS_ERR_INIT(int, SUCCEED)
     trav_visitor_t visitor;             /* Visitor structure for objects */
-    int            ret_value = SUCCEED;
 
     /* Init visitor structure */
     visitor.visit_obj = visit_obj;
@@ -1080,7 +1080,7 @@ done:
 herr_t
 symlink_visit_add(symlink_trav_t *visited, H5L_type_t type, const char *file, const char *path)
 {
-    herr_t    ret_value = SUCCEED;
+    H5TOOLS_ERR_INIT(herr_t, SUCCEED)
     size_t    idx;         /* Index of address to use */
 
     /* Allocate space if necessary */
@@ -1118,7 +1118,7 @@ done:
     return ret_value;
 } /* end symlink_visit_add() */
 
-
+
 /*-------------------------------------------------------------------------
  * Function: symlink_is_visited
  *
diff --git a/tools/src/h5copy/h5copy.c b/tools/src/h5copy/h5copy.c
index ffcd2b9..06240f5 100644
--- a/tools/src/h5copy/h5copy.c
+++ b/tools/src/h5copy/h5copy.c
@@ -207,7 +207,7 @@ static int parse_flag(const char* s_flag, unsigned *flag)
 int
 main (int argc, const char *argv[])
 {
-    int            ret_value = 0; /*no need to LEAVE() on ERROR: H5TOOLS_ERR_INIT(int, SUCCEED) */
+    H5TOOLS_ERR_INIT(int, 0)
     H5E_auto2_t         func;
     H5E_auto2_t         tools_func;
     void               *edata;
diff --git a/tools/src/h5diff/CMakeLists.txt b/tools/src/h5diff/CMakeLists.txt
index 96ed6ad..c1021e4 100644
--- a/tools/src/h5diff/CMakeLists.txt
+++ b/tools/src/h5diff/CMakeLists.txt
@@ -10,6 +10,7 @@ if (NOT ONLY_SHARED_LIBS)
       ${HDF5_TOOLS_SRC_H5DIFF_SOURCE_DIR}/h5diff_main.c
   )
   target_include_directories (h5diff PRIVATE "${HDF5_TOOLS_DIR}/lib;${HDF5_SRC_DIR};${HDF5_BINARY_DIR};$<$<BOOL:${HDF5_ENABLE_PARALLEL}>:${MPI_C_INCLUDE_DIRS}>")
+  #target_compile_definitions(h5diff PRIVATE H5_TOOLS_DEBUG)
   TARGET_C_PROPERTIES (h5diff STATIC)
   target_link_libraries (h5diff PRIVATE ${HDF5_TOOLS_LIB_TARGET} ${HDF5_LIB_TARGET})
   set_target_properties (h5diff PROPERTIES FOLDER tools)
@@ -23,6 +24,7 @@ if (BUILD_SHARED_LIBS)
       ${HDF5_TOOLS_SRC_H5DIFF_SOURCE_DIR}/h5diff_main.c
   )
   target_include_directories (h5diff-shared PRIVATE "${HDF5_TOOLS_DIR}/lib;${HDF5_SRC_DIR};${HDF5_BINARY_DIR};$<$<BOOL:${HDF5_ENABLE_PARALLEL}>:${MPI_C_INCLUDE_DIRS}>")
+  #target_compile_definitions(h5diff-shared PRIVATE H5_TOOLS_DEBUG)
   TARGET_C_PROPERTIES (h5diff-shared SHARED)
   target_link_libraries (h5diff-shared PRIVATE ${HDF5_TOOLS_LIBSH_TARGET} ${HDF5_LIBSH_TARGET})
   set_target_properties (h5diff-shared PROPERTIES FOLDER tools)
diff --git a/tools/src/h5repack/h5repack.c b/tools/src/h5repack/h5repack.c
index 971589e..4fb1507 100644
--- a/tools/src/h5repack/h5repack.c
+++ b/tools/src/h5repack/h5repack.c
@@ -222,10 +222,10 @@ h5repack_addlayout(const char *str, pack_opt_t *options)
 hid_t
 copy_named_datatype(hid_t type_in, hid_t fidout, named_dt_t **named_dt_head_p, trav_table_t *travt, pack_opt_t *options)
 {
+    H5TOOLS_ERR_INIT(hid_t, H5I_INVALID_HID)
     named_dt_t *dt = *named_dt_head_p; /* Stack pointer */
     named_dt_t *dt_ret = NULL;         /* Datatype to return */
     H5O_info_t  oinfo;                 /* Object info of input dtype */
-    hid_t       ret_value = -1;        /* The identifier of the named dtype in the out file */
 
     if (H5Oget_info2(type_in, &oinfo, H5O_INFO_BASIC) < 0)
         H5TOOLS_GOTO_ERROR(FAIL, H5E_tools_min_id_g, "H5Oget_info failed");
@@ -311,8 +311,8 @@ done:
 int
 named_datatype_free(named_dt_t **named_dt_head_p, int ignore_err)
 {
+    H5TOOLS_ERR_INIT(int, -1)
     named_dt_t *dt = *named_dt_head_p;
-    int         ret_value = -1;
 
     while (dt) {
         /* Pop the datatype off the stack and free it */
@@ -343,7 +343,7 @@ done:
 int
 copy_attr(hid_t loc_in, hid_t loc_out, named_dt_t **named_dt_head_p, trav_table_t *travt, pack_opt_t *options)
 {
-    int         ret_value = 0;
+    H5TOOLS_ERR_INIT(int, 0)
     hid_t       attr_id = -1;  /* attr ID */
     hid_t       attr_out = -1; /* attr ID */
     hid_t       space_id = -1; /* space ID */
@@ -546,7 +546,7 @@ done:
 static int
 check_options(pack_opt_t *options)
 {
-    int          ret_value = 0; /*no need to LEAVE() on ERROR: H5TOOLS_ERR_INIT(int, SUCCEED) */
+    H5TOOLS_ERR_INIT(int, 0)
     unsigned int i;
     int          k, j, has_cp = 0, has_ck = 0;
     char         slayout[30];
@@ -724,13 +724,13 @@ done:
 static int
 check_objects(const char* fname, pack_opt_t *options)
 {
+    H5TOOLS_ERR_INIT(int, 0)
     hid_t         fid = -1;
     hid_t         did = -1;
     hid_t         sid = -1;
     unsigned int  i;
     int  ifil;
     trav_table_t *travt = NULL;
-    int           ret_value = 0; /*no need to LEAVE() on ERROR: H5TOOLS_ERR_INIT(int, SUCCEED) */
 
     /* nothing to do */
     if (options->op_tbl->nelems == 0)
diff --git a/tools/src/h5repack/h5repack_copy.c b/tools/src/h5repack/h5repack_copy.c
index 5d41908..2c0af19 100644
--- a/tools/src/h5repack/h5repack_copy.c
+++ b/tools/src/h5repack/h5repack_copy.c
@@ -61,7 +61,7 @@ static void print_user_block(const char *filename, hid_t fid);
 int
 copy_objects(const char* fnamein, const char* fnameout, pack_opt_t *options)
 {
-    int           ret_value = 0;
+    H5TOOLS_ERR_INIT(int, 0)
     hid_t         fidin = -1;
     hid_t         fidout = -1;
     hid_t         fcpl_in = -1;  /* file creation property list ID for input file */
@@ -402,7 +402,7 @@ int
 get_hyperslab(hid_t dcpl_id, int rank_dset, hsize_t dims_dset[],
         size_t size_datum, hsize_t dims_hslab[], hsize_t * hslab_nbytes_p)
 {
-    int     ret_value = 0;
+    H5TOOLS_ERR_INIT(int, 0)
     int     k;
     H5D_layout_t dset_layout;
     int     rank_chunk;
@@ -580,7 +580,7 @@ int
 do_copy_objects(hid_t fidin, hid_t fidout, trav_table_t *travt,
         pack_opt_t *options) /* repack options */
 {
-    int   ret_value = 0;
+    H5TOOLS_ERR_INIT(int, 0)
     hid_t grp_in = -1;   /* group ID */
     hid_t grp_out = -1;  /* group ID */
     hid_t dset_in = -1;  /* read dataset ID */
@@ -1354,7 +1354,7 @@ print_dataset_info(hid_t dcpl_id, char *objname, double ratio, int pr)
 static int
 copy_user_block(const char *infile, const char *outfile, hsize_t size)
 {
-    int ret_value = 0;
+    H5TOOLS_ERR_INIT(int, 0)
     int infid = -1, outfid = -1; /* File descriptors */
 
     /* User block must be any power of 2 equal to 512 or greater (512, 1024, 2048, etc.) */
@@ -1426,7 +1426,7 @@ static
 void
 print_user_block(const char *filename, hid_t fid)
 {
-    int     ret_value = 0;
+    H5TOOLS_ERR_INIT(int, 0)
     int     fh = -1;   /* file handle */
     hsize_t ub_size;   /* user block size */
     hsize_t size;      /* size read */
diff --git a/tools/src/h5repack/h5repack_filters.c b/tools/src/h5repack/h5repack_filters.c
index 891de25..9eb7c89 100644
--- a/tools/src/h5repack/h5repack_filters.c
+++ b/tools/src/h5repack/h5repack_filters.c
@@ -36,7 +36,7 @@ static int aux_copy_obj(hid_t dcpl_id, /* dataset creation property list */
         const char* name,              /* object name from traverse list */
         pack_info_t *objout /*OUT*/)   /* info about object to filter */
 {
-    int          ret_value = 0;  /*no need to LEAVE() on ERROR: H5TOOLS_ERR_INIT(int, SUCCEED) */
+    H5TOOLS_ERR_INIT(int, 0)
     int          nfilters;       /* number of filters in DCPL */
     char         f_objname[256]; /* filter objname */
     H5D_layout_t layout;
@@ -238,7 +238,7 @@ int apply_filters(const char* name, /* object name from traverse list */
         pack_opt_t *options,        /* repack options */
         int *has_filter)            /* (OUT) object NAME has a filter */
 {
-    int         ret_value = 0; /*no need to LEAVE() on ERROR: H5TOOLS_ERR_INIT(int, SUCCEED) */
+    H5TOOLS_ERR_INIT(int, 0)
     int         nfilters;      /* number of filters in DCPL */
     hsize_t     chsize[64];    /* chunk size in elements */
     H5D_layout_t layout;
diff --git a/tools/src/h5repack/h5repack_opttable.c b/tools/src/h5repack/h5repack_opttable.c
index 9d35c4f..0239f6c 100644
--- a/tools/src/h5repack/h5repack_opttable.c
+++ b/tools/src/h5repack/h5repack_opttable.c
@@ -24,7 +24,8 @@
   *-------------------------------------------------------------------------
  */
 
-void init_packobject(pack_info_t *obj) {
+void init_packobject(pack_info_t *obj)
+{
     int j, k;
 
     HDstrcpy(obj->path, "\0");
@@ -49,7 +50,9 @@ void init_packobject(pack_info_t *obj) {
  *-------------------------------------------------------------------------
  */
 
-static void aux_tblinsert_filter(pack_opttbl_t *table, unsigned int I, filter_info_t filt) {
+static void aux_tblinsert_filter(pack_opttbl_t *table, unsigned int I, filter_info_t filt)
+{
+    H5TOOLS_ERR_INIT(int, 0)
     if (table->objs[I].nfilters < H5_REPACK_MAX_NFILTERS)
         table->objs[I].filter[table->objs[I].nfilters++] = filt;
     else
@@ -64,7 +67,8 @@ static void aux_tblinsert_filter(pack_opttbl_t *table, unsigned int I, filter_in
  * Return: void
  *-------------------------------------------------------------------------
  */
-static void aux_tblinsert_layout(pack_opttbl_t *table, unsigned int I, pack_info_t *pack) {
+static void aux_tblinsert_layout(pack_opttbl_t *table, unsigned int I, pack_info_t *pack)
+{
     int k;
 
     table->objs[I].layout = pack->layout;
@@ -96,19 +100,21 @@ static void aux_tblinsert_layout(pack_opttbl_t *table, unsigned int I, pack_info
 static int
 aux_inctable(pack_opttbl_t *table, unsigned n_objs)
 {
+    H5TOOLS_ERR_INIT(int, 0)
     unsigned u;
 
     table->size += n_objs;
     table->objs = (pack_info_t*) HDrealloc(table->objs, table->size * sizeof(pack_info_t));
     if (table->objs == NULL) {
         H5TOOLS_INFO(H5E_tools_min_id_g, "not enough memory for options table");
-        return -1;
+        ret_value = -1;
+    }
+    else {
+        for (u = table->nelems; u < table->size; u++)
+            init_packobject(&table->objs[u]);
     }
 
-    for (u = table->nelems; u < table->size; u++)
-        init_packobject(&table->objs[u]);
-
-    return 0;
+    return ret_value;
 }
 
 
@@ -121,27 +127,27 @@ aux_inctable(pack_opttbl_t *table, unsigned n_objs)
   *-------------------------------------------------------------------------
  */
 int options_table_init(pack_opttbl_t **tbl) {
+    H5TOOLS_ERR_INIT(int, 0)
     unsigned int i;
     pack_opttbl_t *table;
 
     if (NULL == (table = (pack_opttbl_t *) HDmalloc(sizeof(pack_opttbl_t)))) {
-        H5TOOLS_INFO(H5E_tools_min_id_g, "not enough memory for options table");
-        return -1;
+        H5TOOLS_GOTO_ERROR(-1, H5E_tools_min_id_g, "not enough memory for options table");
     }
 
     table->size = 30;
     table->nelems = 0;
     if (NULL == (table->objs = (pack_info_t*) HDmalloc(table->size * sizeof(pack_info_t)))) {
-        H5TOOLS_INFO(H5E_tools_min_id_g, "not enough memory for options table");
         HDfree(table);
-        return -1;
+        H5TOOLS_GOTO_ERROR(-1, H5E_tools_min_id_g, "not enough memory for options table");
     }
 
     for (i = 0; i < table->size; i++)
         init_packobject(&table->objs[i]);
 
     *tbl = table;
-    return 0;
+done:
+    return ret_value;
 }
 
 
@@ -171,6 +177,7 @@ int options_table_free(pack_opttbl_t *table) {
 int
 options_add_layout(obj_list_t *obj_list, unsigned  n_objs, pack_info_t *pack, pack_opttbl_t *table)
 {
+    H5TOOLS_ERR_INIT(herr_t, 0)
     unsigned i, j, I;
     unsigned added = 0;
     hbool_t found = FALSE;
@@ -237,7 +244,7 @@ options_add_layout(obj_list_t *obj_list, unsigned  n_objs, pack_info_t *pack, pa
 
     table->nelems += added;
 
-    return 0;
+    return ret_value;
 }
 
 /*-------------------------------------------------------------------------
diff --git a/tools/src/h5repack/h5repack_refs.c b/tools/src/h5repack/h5repack_refs.c
index 52917fb..02a2a6d 100644
--- a/tools/src/h5repack/h5repack_refs.c
+++ b/tools/src/h5repack/h5repack_refs.c
@@ -42,7 +42,7 @@ int do_copy_refobjs(hid_t fidin,
                     trav_table_t *travt,
                     pack_opt_t *options) /* repack options */
 {
-    int       ret_value = 0;          /*no need to LEAVE() on ERROR: H5TOOLS_ERR_INIT(int, SUCCEED) */
+    H5TOOLS_ERR_INIT(int, 0)
     hid_t     grp_in = -1;            /* read group ID */
     hid_t     grp_out = -1;           /* write group ID */
     hid_t     dset_in = -1;           /* read dataset ID */
@@ -429,7 +429,7 @@ static int copy_refs_attr(hid_t loc_in,
                           trav_table_t *travt,
                           hid_t fidout)         /* for saving references */
 {
-    int         ret_value = 0;     /*no need to LEAVE() on ERROR: H5TOOLS_ERR_INIT(int, SUCCEED) */
+    H5TOOLS_ERR_INIT(int, 0)
     hid_t       attr_id = -1;      /* attr ID */
     hid_t       attr_out = -1;     /* attr ID */
     hid_t       space_id = -1;     /* space ID */
@@ -822,7 +822,7 @@ out:
 static herr_t update_ref_value(hid_t obj_id, H5R_type_t ref_type, void *ref_in,
         hid_t fid_out, void *ref_out, trav_table_t *travt)
 {
-    int         ret_value = 0;   /*no need to LEAVE() on ERROR: H5TOOLS_ERR_INIT(int, SUCCEED) */
+    H5TOOLS_ERR_INIT(int, 0)
     const char *ref_obj_name;
     hid_t       space_id = -1;
     hid_t       ref_obj_id = -1;
diff --git a/tools/src/h5repack/h5repack_verify.c b/tools/src/h5repack/h5repack_verify.c
index 30bd3f6..29ce5bd 100644
--- a/tools/src/h5repack/h5repack_verify.c
+++ b/tools/src/h5repack/h5repack_verify.c
@@ -39,7 +39,7 @@ static int verify_filters(hid_t pid, hid_t tid, int nfilters, filter_info_t *fil
 int
 h5repack_verify(const char *in_fname, const char *out_fname, pack_opt_t *options)
 {
-    int          ret_value  = 0;    /*no need to LEAVE() on ERROR: H5TOOLS_ERR_INIT(int, SUCCEED) */
+    H5TOOLS_ERR_INIT(int, 0)
     hid_t        fidin      = -1;   /* file ID for input file*/
     hid_t        fidout     = -1;   /* file ID for output file*/
     hid_t        did        = -1;   /* dataset ID */
@@ -355,7 +355,7 @@ int verify_layout(hid_t pid, pack_info_t *obj)
 
 int h5repack_cmp_pl(const char *fname1, const char *fname2)
 {
-    int           ret_value = 1;    /*no need to LEAVE() on ERROR: H5TOOLS_ERR_INIT(int, SUCCEED) */
+    H5TOOLS_ERR_INIT(int, 1)
     hid_t         fid1 =-1;         /* file ID */
     hid_t         fid2 =-1;         /* file ID */
     hid_t         dset1 =-1;        /* dataset ID */
diff --git a/tools/src/h5stat/h5stat.c b/tools/src/h5stat/h5stat.c
index 6ff1e8c..64053a8 100644
--- a/tools/src/h5stat/h5stat.c
+++ b/tools/src/h5stat/h5stat.c
@@ -442,9 +442,9 @@ attribute_stats(iter_t *iter, const H5O_info_t *oi)
 static herr_t
 group_stats(iter_t *iter, const char *name, const H5O_info_t *oi)
 {
+    H5TOOLS_ERR_INIT(herr_t, SUCCEED)
     H5G_info_t ginfo;           /* Group information */
     unsigned bin;               /* "bin" the number of objects falls in */
-    herr_t ret_value = SUCCEED; /* Return value */
 
     /* Gather statistics about this type of object */
     iter->uniq_groups++;
@@ -512,6 +512,7 @@ done:
 static herr_t
 dataset_stats(iter_t *iter, const char *name, const H5O_info_t *oi)
 {
+    H5TOOLS_ERR_INIT(herr_t, SUCCEED)
     unsigned bin;               /* "bin" the number of objects falls in */
     hid_t did;                  /* Dataset ID */
     hid_t sid;                  /* Dataspace ID */
@@ -527,7 +528,6 @@ dataset_stats(iter_t *iter, const char *name, const H5O_info_t *oi)
     int num_ext;                /* Number of external files for a dataset */
     int nfltr;                  /* Number of filters for a dataset */
     H5Z_filter_t fltr;          /* Filter identifier */
-    herr_t ret_value = SUCCEED; /* Return value */
 
     /* Gather statistics about this type of object */
     iter->uniq_dsets++;
@@ -704,7 +704,7 @@ done:
 static herr_t
 datatype_stats(iter_t *iter, const H5O_info_t *oi)
 {
-    herr_t ret_value = SUCCEED;
+    H5TOOLS_ERR_INIT(herr_t, SUCCEED)
 
     /* Gather statistics about this type of object */
     iter->uniq_dtypes++;
@@ -738,8 +738,8 @@ static herr_t
 obj_stats(const char *path, const H5O_info_t *oi, const char *already_visited,
     void *_iter)
 {
+    H5TOOLS_ERR_INIT(herr_t, SUCCEED)
     iter_t *iter = (iter_t *)_iter;
-    herr_t ret_value = SUCCEED;
 
     /* If the object has already been seen then just return */
     if(NULL == already_visited) {
diff --git a/tools/test/h5diff/CMakeTests.cmake b/tools/test/h5diff/CMakeTests.cmake
index 57bcd12..d03926a 100644
--- a/tools/test/h5diff/CMakeTests.cmake
+++ b/tools/test/h5diff/CMakeTests.cmake
@@ -94,6 +94,17 @@
       ${HDF5_TOOLS_DIR}/testfiles/vds/5_vds.h5
       # tools/testfiles
       ${HDF5_TOOLS_DIR}/testfiles/tvlstr.h5
+      #STD_REF_OBJ files
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_attr.h5
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_compat.h5
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_ext1.h5
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_ext2.h5
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_grp.h5
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_obj_del.h5
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_obj.h5
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_param.h5
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_reg_1d.h5
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_reg.h5
   )
 
   set (LIST_OTHER_TEST_FILES
@@ -1044,7 +1055,10 @@ ADD_H5_TEST (h5diff_56 1 -v ${FILE4} ${FILE4} dset6a dset6b)
 ADD_H5_TEST (h5diff_57 0 -v ${FILE4} ${FILE4} dset7a dset7b)
 
 # 5.8 (region reference)
-ADD_H5_TEST (h5diff_58 1 -v ${FILE7} ${FILE8} refreg)
+ADD_H5_TEST (h5diff_58 1 -v2 ${FILE7} ${FILE8} refreg)
+ADD_H5_TEST (h5diff_58_ref 1 -v2 ${FILE7} ${FILE8} /g1/reference2D)
+# STD_REF_OBJ
+ADD_H5_TEST (h5diff_reg 0 -v2 trefer_attr.h5 trefer_ext2.h5 Dataset3 Dataset3)
 
 # test for both dset and attr with same type but with different size
 # ( HDDFV-7942 )
@@ -1484,8 +1498,6 @@ ADD_H5_TEST (h5diff_485 0 -v --exclude-path "/group1" h5diff_exclude3-1.h5 h5dif
 ADD_H5_TEST (h5diff_486 0 -v --exclude-path "/group1" h5diff_exclude3-2.h5 h5diff_exclude3-1.h5)
 ADD_H5_TEST (h5diff_487 1 -v --exclude-path "/group1/dset" h5diff_exclude3-1.h5 h5diff_exclude3-2.h5)
 
-
-
 # ##############################################################################
 # # diff various multiple vlen and fixed strings in a compound type dataset
 # ##############################################################################
@@ -1524,7 +1536,7 @@ ADD_H5_TEST (h5diff_800 1 -v ${FILE7} ${FILE8} /g1/array /g1/array)
 ADD_H5_TEST (h5diff_801 1 -v ${FILE7} ${FILE8A} /g1/array /g1/array)
 
 # ##############################################################################
-# VDS tests
+# # VDS tests
 # ##############################################################################
 ADD_H5_TEST (h5diff_v1 0 -v ${FILEV1} ${FILEV2})
 ADD_H5_TEST (h5diff_v2 0 -r ${FILEV1} ${FILEV2})
diff --git a/tools/test/h5diff/testfiles/h5diff_58.txt b/tools/test/h5diff/testfiles/h5diff_58.txt
index d27a0c9..da147bc 100644
--- a/tools/test/h5diff/testfiles/h5diff_58.txt
+++ b/tools/test/h5diff/testfiles/h5diff_58.txt
@@ -1,3 +1,4 @@
+
 dataset: </refreg> and </refreg>
 Referenced dataset      10784            10784
 ------------------------------------------------------------
@@ -8,4 +9,7 @@ point #1              (2,2)              (3,3)
 point #3              (1,6)              (2,5)
 point #4              (2,8)              (1,7)
 4 differences found
+   obj1   obj2
+ --------------------------------------
+Attributes status:  0 common, 0 only in obj1, 0 only in obj2
 EXIT CODE: 1
diff --git a/tools/test/h5diff/testfiles/h5diff_58_ref.txt b/tools/test/h5diff/testfiles/h5diff_58_ref.txt
new file mode 100644
index 0000000..6fa2299
--- /dev/null
+++ b/tools/test/h5diff/testfiles/h5diff_58_ref.txt
@@ -0,0 +1,37 @@
+
+dataset: </g1/reference2D> and </g1/reference2D>
+size:           [2]           [2]
+position                                        difference          
+------------------------------------------------------------
+[ 0 ]          1               0               1              
+[ 1 ]          2               0               2              
+size:           [2]           [2]
+position                                        difference          
+------------------------------------------------------------
+[ 0 ]          1               0               1              
+[ 1 ]          2               0               2              
+size:           [2]           [2]
+position                                        difference          
+------------------------------------------------------------
+[ 0 ]          1               0               1              
+[ 1 ]          2               0               2              
+size:           [2]           [2]
+position                                        difference          
+------------------------------------------------------------
+[ 0 ]          1               0               1              
+[ 1 ]          2               0               2              
+size:           [2]           [2]
+position                                        difference          
+------------------------------------------------------------
+[ 0 ]          1               0               1              
+[ 1 ]          2               0               2              
+size:           [2]           [2]
+position                                        difference          
+------------------------------------------------------------
+[ 0 ]          1               0               1              
+[ 1 ]          2               0               2              
+12 differences found
+   obj1   obj2
+ --------------------------------------
+Attributes status:  0 common, 0 only in obj1, 0 only in obj2
+EXIT CODE: 1
diff --git a/tools/test/h5diff/testfiles/h5diff_reg.txt b/tools/test/h5diff/testfiles/h5diff_reg.txt
new file mode 100644
index 0000000..19dae48
--- /dev/null
+++ b/tools/test/h5diff/testfiles/h5diff_reg.txt
@@ -0,0 +1,15 @@
+
+dataset: </Dataset3> and </Dataset3>
+attribute: <Attr1> and <Attr1>
+0 differences found
+Warning: Cannot open referenced attribute: attribute 1
+Warning: Cannot open referenced attribute: attribute 2
+attribute: <Attr2> and <Attr2>
+0 differences found
+attribute: <Attr3> and <Attr3>
+0 differences found
+0 differences found
+   obj1   obj2
+ --------------------------------------
+Attributes status:  0 common, 0 only in obj1, 0 only in obj2
+EXIT CODE: 0
diff --git a/tools/test/h5dump/CMakeTests.cmake b/tools/test/h5dump/CMakeTests.cmake
index 62b2619..2e731f3 100644
--- a/tools/test/h5dump/CMakeTests.cmake
+++ b/tools/test/h5dump/CMakeTests.cmake
@@ -198,6 +198,16 @@
       ${HDF5_TOOLS_DIR}/testfiles/h5dump-help.txt
       ${HDF5_TOOLS_DIR}/testfiles/out3.h5import
       ${HDF5_TOOLS_DIR}/testfiles/zerodim.ddl
+      #STD_REF_OBJ files
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_attrR.ddl
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_compatR.ddl
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_extR.ddl
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_grpR.ddl
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_obj_delR.ddl
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_objR.ddl
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_paramR.ddl
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_reg_1dR.ddl
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_regR.ddl
   )
   set (HDF5_N_REFERENCE_FILES
       tall-3
@@ -322,6 +332,18 @@
       ${HDF5_TOOLS_DIR}/testfiles/tvms.h5
       ${HDF5_TOOLS_DIR}/testfiles/t128bit_float.h5
       ${HDF5_TOOLS_DIR}/testfiles/zerodim.h5
+      #STD_REF_OBJ files
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_attr.h5
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_compat.h5
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_ext1.h5
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_ext2.h5
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_grp.h5
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_obj_del.h5
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_obj.h5
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_param.h5
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_reg_1d.h5
+      ${HDF5_TOOLS_DIR}/testfiles/trefer_reg.h5
+
   )
   set (HDF5_ERROR_REFERENCE_TEST_FILES
       ${PROJECT_SOURCE_DIR}/errfiles/filter_fail.err
@@ -1108,6 +1130,17 @@
   ADD_H5ERR_MASK_TEST (tattrregR 0 "NULL token size" -R --enable-error-stack tattrreg.h5)
   ADD_H5_EXPORT_TEST (tbinregR tdatareg.h5 0 --enable-error-stack -d /Dataset1 -s 0 -R -y -o)
 
+  # test for 1.12 region references
+  ADD_H5_TEST (trefer_attrR 0 --enable-error-stack -R trefer_attr.h5)
+  ADD_H5_TEST (trefer_compatR 0 --enable-error-stack -R trefer_compat.h5)
+  ADD_H5_TEST (trefer_extR 0 --enable-error-stack -R trefer_ext2.h5)
+  ADD_H5_TEST (trefer_grpR 0 --enable-error-stack -R trefer_grp.h5)
+  ADD_H5_TEST (trefer_obj_delR 0 --enable-error-stack -R trefer_obj_del.h5)
+  ADD_H5_TEST (trefer_objR 0 --enable-error-stack -R trefer_obj.h5)
+  ADD_H5_TEST (trefer_paramR 0 --enable-error-stack -R trefer_param.h5)
+  ADD_H5_TEST (trefer_regR 0 --enable-error-stack -R trefer_reg.h5)
+  ADD_H5_TEST (trefer_reg_1dR 0 --enable-error-stack -R trefer_reg_1d.h5)
+
   # tests for group creation order
   # "1" tracked, "2" name, root tracked
   ADD_H5_TEST (tordergr1 0 --enable-error-stack --group=1 --sort_by=creation_order --sort_order=ascending tordergr.h5)
diff --git a/tools/test/perform/pio_standalone.c b/tools/test/perform/pio_standalone.c
index dd6a61a..f6866bb 100644
--- a/tools/test/perform/pio_standalone.c
+++ b/tools/test/perform/pio_standalone.c
@@ -161,5 +161,3 @@ print_version(const char *progname)
            progname, H5_VERS_MAJOR, H5_VERS_MINOR, H5_VERS_RELEASE,
            H5_VERS_SUBRELEASE[0] ? "-" : "", H5_VERS_SUBRELEASE);
 }
-
-
diff --git a/tools/testfiles/trefer_attr.h5 b/tools/testfiles/trefer_attr.h5
new file mode 100644
index 0000000..3110ce3
--- /dev/null
+++ b/tools/testfiles/trefer_attr.h5
diff --git a/tools/testfiles/trefer_attrR.ddl b/tools/testfiles/trefer_attrR.ddl
new file mode 100644
index 0000000..e64c8e6
--- /dev/null
+++ b/tools/testfiles/trefer_attrR.ddl
@@ -0,0 +1,76 @@
+HDF5 "trefer_attr.h5" {
+GROUP "/" {
+   DATASET "Dataset3" {
+      DATATYPE  H5T_REFERENCE { H5T_STD_REF }
+      DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+      DATA {
+         ATTRIBUTE "trefer_attr.h5/Group1/Dataset1/Attr1" {
+            DATATYPE  H5T_STD_U32LE
+            DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+            DATA {
+            (0): 0, 3, 6, 9
+            }
+         }
+         ATTRIBUTE "trefer_attr.h5/Group1/Dataset2/Attr1" {
+               NULL
+         }
+         ATTRIBUTE "trefer_attr.h5/Group1/Attr2"  {
+            DATATYPE  H5T_STD_U32LE
+            DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+            DATA {
+            (0): 1, 4, 7, 10
+            }
+         }
+         ATTRIBUTE "trefer_attr.h5/Group1/Datatype1/Attr3"  {
+            DATATYPE  H5T_STD_U32LE
+            DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+            DATA {
+            (0): 2, 5, 8, 11
+            }
+         }
+      }
+   }
+   GROUP "Group1" {
+      ATTRIBUTE "Attr2" {
+         DATATYPE  H5T_STD_U32LE
+         DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+         DATA {
+         (0): 1, 4, 7, 10
+         }
+      }
+      DATASET "Dataset1" {
+         DATATYPE  H5T_STD_U32LE
+         DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+         DATA {
+         (0): 0, 0, 0, 0
+         }
+         ATTRIBUTE "Attr1" {
+            DATATYPE  H5T_STD_U32LE
+            DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+            DATA {
+            (0): 0, 3, 6, 9
+            }
+         }
+      }
+      DATASET "Dataset2" {
+         DATATYPE  H5T_STD_U8LE
+         DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+         DATA {
+         (0): 0, 0, 0, 0
+         }
+      }
+      DATATYPE "Datatype1" H5T_COMPOUND {
+         H5T_STD_I32LE "a";
+         H5T_STD_I32LE "b";
+         H5T_IEEE_F32LE "c";
+      }
+         ATTRIBUTE "Attr3" {
+            DATATYPE  H5T_STD_U32LE
+            DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+            DATA {
+            (0): 2, 5, 8, 11
+            }
+         }
+   }
+}
+}
diff --git a/tools/testfiles/trefer_compat.h5 b/tools/testfiles/trefer_compat.h5
new file mode 100644
index 0000000..5f6dd60
--- /dev/null
+++ b/tools/testfiles/trefer_compat.h5
diff --git a/tools/testfiles/trefer_compatR.ddl b/tools/testfiles/trefer_compatR.ddl
new file mode 100644
index 0000000..97c7934
--- /dev/null
+++ b/tools/testfiles/trefer_compatR.ddl
@@ -0,0 +1,114 @@
+HDF5 "trefer_compat.h5" {
+GROUP "/" {
+   DATASET "Dataset3" {
+      DATATYPE  H5T_REFERENCE { H5T_STD_REF_OBJECT }
+      DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+      DATA {
+         DATASET "trefer_compat.h5/Group1/Dataset1"
+            DATA {
+            (0,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            (1,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            (2,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            (3,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            (4,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            (5,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            (6,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            (7,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            (8,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            (9,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+            }
+         DATASET "trefer_compat.h5/Group1/Dataset2"
+            DATA {
+            (0,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            (1,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            (2,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            (3,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            (4,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            (5,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            (6,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            (7,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            (8,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            (9,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+            }
+         GROUP "trefer_compat.h5/Group1"
+         DATATYPE "trefer_compat.h5/Group1/Datatype1"
+      }
+   }
+   DATASET "Dataset4" {
+      DATATYPE  H5T_REFERENCE { H5T_STD_REF_DSETREG }
+      DATASPACE  SIMPLE { ( 2 ) / ( 2 ) }
+      DATA {
+         DATASET "trefer_compat.h5/Group1/Dataset1" {
+            REGION_TYPE BLOCK  (2,2)-(7,7)
+            DATATYPE  H5T_STD_U32LE
+            DATASPACE  SIMPLE { ( 10, 10 ) / ( 10, 10 ) }
+            DATA {
+               0, 0, 0, 0, 0, 0,
+               0, 0, 0, 0, 0, 0,
+               0, 0, 0, 0, 0, 0,
+               0, 0, 0, 0, 0, 0,
+               0, 0, 0, 0, 0, 0,
+               0, 0, 0, 0, 0, 0
+            }
+         }
+         DATASET "trefer_compat.h5/Group1/Dataset2" {
+            REGION_TYPE POINT  (6,9), (2,2), (8,4), (1,6), (2,8), (3,2),
+             (0,4), (9,0), (7,1), (3,3)
+            DATATYPE  H5T_STD_U8LE
+            DATASPACE  SIMPLE { ( 10, 10 ) / ( 10, 10 ) }
+            DATA {
+               0,
+               0,
+               0,
+               0,
+               0,
+               0,
+               0,
+               0,
+               0,
+               0
+            }
+         }
+      }
+   }
+   GROUP "Group1" {
+      DATASET "Dataset1" {
+         DATATYPE  H5T_STD_U32LE
+         DATASPACE  SIMPLE { ( 10, 10 ) / ( 10, 10 ) }
+         DATA {
+         (0,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+         (1,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+         (2,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+         (3,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+         (4,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+         (5,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+         (6,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+         (7,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+         (8,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+         (9,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+         }
+      }
+      DATASET "Dataset2" {
+         DATATYPE  H5T_STD_U8LE
+         DATASPACE  SIMPLE { ( 10, 10 ) / ( 10, 10 ) }
+         DATA {
+         (0,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+         (1,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+         (2,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+         (3,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+         (4,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+         (5,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+         (6,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+         (7,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+         (8,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+         (9,0): 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+         }
+      }
+      DATATYPE "Datatype1" H5T_COMPOUND {
+         H5T_STD_I32LE "a";
+         H5T_STD_I32LE "b";
+         H5T_IEEE_F32LE "c";
+      }
+   }
+}
+}
diff --git a/tools/testfiles/trefer_ext1.h5 b/tools/testfiles/trefer_ext1.h5
new file mode 100644
index 0000000..9fc9741
--- /dev/null
+++ b/tools/testfiles/trefer_ext1.h5
diff --git a/tools/testfiles/trefer_ext2.h5 b/tools/testfiles/trefer_ext2.h5
new file mode 100644
index 0000000..fcbb75d
--- /dev/null
+++ b/tools/testfiles/trefer_ext2.h5
diff --git a/tools/testfiles/trefer_extR.ddl b/tools/testfiles/trefer_extR.ddl
new file mode 100644
index 0000000..3d4647d
--- /dev/null
+++ b/tools/testfiles/trefer_extR.ddl
@@ -0,0 +1,34 @@
+HDF5 "trefer_ext2.h5" {
+GROUP "/" {
+   DATASET "Dataset3" {
+      DATATYPE  H5T_REFERENCE { H5T_STD_REF }
+      DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+      DATA {
+         ATTRIBUTE "trefer_ext1.h5/Group1/Dataset1/Attr1" {
+            DATATYPE  H5T_STD_U32LE
+            DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+            DATA {
+            (0): 0, 3, 6, 9
+            }
+         }
+         ATTRIBUTE "trefer_ext1.h5/Group1/Dataset2/Attr1" {
+               NULL
+         }
+         ATTRIBUTE "trefer_ext1.h5/Group1/Attr2"  {
+            DATATYPE  H5T_STD_U32LE
+            DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+            DATA {
+            (0): 1, 4, 7, 10
+            }
+         }
+         ATTRIBUTE "trefer_ext1.h5/Group1/Datatype1/Attr3"  {
+            DATATYPE  H5T_STD_U32LE
+            DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+            DATA {
+            (0): 2, 5, 8, 11
+            }
+         }
+      }
+   }
+}
+}
diff --git a/tools/testfiles/trefer_grp.h5 b/tools/testfiles/trefer_grp.h5
new file mode 100644
index 0000000..d846e75
--- /dev/null
+++ b/tools/testfiles/trefer_grp.h5
diff --git a/tools/testfiles/trefer_grpR.ddl b/tools/testfiles/trefer_grpR.ddl
new file mode 100644
index 0000000..298b836
--- /dev/null
+++ b/tools/testfiles/trefer_grpR.ddl
@@ -0,0 +1,15 @@
+HDF5 "trefer_grp.h5" {
+GROUP "/" {
+   DATASET "dset" {
+      DATATYPE  H5T_REFERENCE { H5T_STD_REF }
+      DATASPACE  SCALAR
+      DATA {
+         GROUP "trefer_grp.h5/group"
+      }
+   }
+   GROUP "group" {
+      GROUP "group3" {
+      }
+   }
+}
+}
diff --git a/tools/testfiles/trefer_obj.h5 b/tools/testfiles/trefer_obj.h5
new file mode 100644
index 0000000..de4c19d
--- /dev/null
+++ b/tools/testfiles/trefer_obj.h5
diff --git a/tools/testfiles/trefer_objR.ddl b/tools/testfiles/trefer_objR.ddl
new file mode 100644
index 0000000..0d5af28
--- /dev/null
+++ b/tools/testfiles/trefer_objR.ddl
@@ -0,0 +1,59 @@
+HDF5 "trefer_obj.h5" {
+GROUP "/" {
+   DATASET "Dataset3" {
+      DATATYPE  H5T_REFERENCE { H5T_STD_REF }
+      DATASPACE  SIMPLE { ( 1 ) / ( 1 ) }
+      DATA {
+         DATASET "trefer_obj.h5/Group1/Dataset1"
+            DATA {
+            (0): 0
+            }
+      }
+   }
+   DATASET "Dataset4" {
+      DATATYPE  H5T_REFERENCE { H5T_STD_REF_OBJECT }
+      DATASPACE  SIMPLE { ( 1 ) / ( 1 ) }
+      DATA {
+         DATASET "trefer_obj.h5/Group1/Dataset1"
+            DATA {
+            (0): 0
+            }
+      }
+   }
+   DATASET "Dataset5" {
+      DATATYPE  H5T_REFERENCE { H5T_STD_REF }
+      DATASPACE  SIMPLE { ( 1 ) / ( 1 ) }
+      DATA {
+         DATASET "trefer_obj.h5/Group1/Dataset1"
+      }
+   }
+   DATASET "Dataset6" {
+      DATATYPE  H5T_REFERENCE { H5T_STD_REF_DSETREG }
+      DATASPACE  SIMPLE { ( 1 ) / ( 1 ) }
+      DATA {
+         DATASET "trefer_obj.h5/Group1/Dataset1"
+      }
+   }
+   GROUP "Group1" {
+      DATASET "Dataset1" {
+         DATATYPE  H5T_STD_U32LE
+         DATASPACE  SIMPLE { ( 1 ) / ( 1 ) }
+         DATA {
+         (0): 0
+         }
+      }
+      DATASET "Dataset2" {
+         DATATYPE  H5T_STD_U8LE
+         DATASPACE  SIMPLE { ( 1 ) / ( 1 ) }
+         DATA {
+         (0): 0
+         }
+      }
+      DATATYPE "Datatype1" H5T_COMPOUND {
+         H5T_STD_I32LE "a";
+         H5T_STD_I32LE "b";
+         H5T_IEEE_F32LE "c";
+      }
+   }
+}
+}
diff --git a/tools/testfiles/trefer_obj_del.h5 b/tools/testfiles/trefer_obj_del.h5
new file mode 100644
index 0000000..c1710e8
--- /dev/null
+++ b/tools/testfiles/trefer_obj_del.h5
diff --git a/tools/testfiles/trefer_obj_delR.ddl b/tools/testfiles/trefer_obj_delR.ddl
new file mode 100644
index 0000000..598998d
--- /dev/null
+++ b/tools/testfiles/trefer_obj_delR.ddl
@@ -0,0 +1,11 @@
+HDF5 "trefer_obj_del.h5" {
+GROUP "/" {
+   DATASET "Dataset2" {
+      DATATYPE  H5T_REFERENCE { H5T_STD_REF }
+      DATASPACE  SCALAR
+      DATA {
+         GROUP "trefer_obj_del.h5"
+      }
+   }
+}
+}
diff --git a/tools/testfiles/trefer_param.h5 b/tools/testfiles/trefer_param.h5
new file mode 100644
index 0000000..234629a
--- /dev/null
+++ b/tools/testfiles/trefer_param.h5
diff --git a/tools/testfiles/trefer_paramR.ddl b/tools/testfiles/trefer_paramR.ddl
new file mode 100644
index 0000000..ce9fa86
--- /dev/null
+++ b/tools/testfiles/trefer_paramR.ddl
@@ -0,0 +1,43 @@
+HDF5 "trefer_param.h5" {
+GROUP "/" {
+   DATASET "Dataset3" {
+      DATATYPE  H5T_REFERENCE { H5T_STD_REF }
+      DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+      DATA {
+         NULL
+         NULL
+         NULL
+         NULL
+      }
+   }
+   GROUP "Group1" {
+      COMMENT "Foo!"
+      DATASET "Dataset1" {
+         DATATYPE  H5T_STD_U32LE
+         DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+         DATA {
+         (0): 0, 3, 6, 9
+         }
+      }
+      DATASET "Dataset2" {
+         DATATYPE  H5T_STD_U8LE
+         DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+         DATA {
+         (0): 0, 0, 0, 0
+         }
+         ATTRIBUTE "Attr" {
+            DATATYPE  H5T_STD_U32LE
+            DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+            DATA {
+            (0): 0, 3, 6, 9
+            }
+         }
+      }
+      DATATYPE "Datatype1" H5T_COMPOUND {
+         H5T_STD_I32LE "a";
+         H5T_STD_I32LE "b";
+         H5T_IEEE_F32LE "c";
+      }
+   }
+}
+}
diff --git a/tools/testfiles/trefer_reg.h5 b/tools/testfiles/trefer_reg.h5
new file mode 100644
index 0000000..8ed9184
--- /dev/null
+++ b/tools/testfiles/trefer_reg.h5
diff --git a/tools/testfiles/trefer_regR.ddl b/tools/testfiles/trefer_regR.ddl
new file mode 100644
index 0000000..683c196
--- /dev/null
+++ b/tools/testfiles/trefer_regR.ddl
@@ -0,0 +1,66 @@
+HDF5 "trefer_reg.h5" {
+GROUP "/" {
+   DATASET "DS_NA" {
+      DATATYPE  H5T_REFERENCE { H5T_STD_REF }
+      DATASPACE  SIMPLE { ( 1 ) / ( 1 ) }
+      DATA {
+         NULL
+      }
+   }
+   DATASET "Dataset1" {
+      DATATYPE  H5T_REFERENCE { H5T_STD_REF }
+      DATASPACE  SIMPLE { ( 4 ) / ( 4 ) }
+      DATA {
+         DATASET "trefer_reg.h5/Dataset2" {
+            REGION_TYPE BLOCK  (2,2)-(7,7)
+            DATATYPE  H5T_STD_U8LE
+            DATASPACE  SIMPLE { ( 10, 10 ) / ( 10, 10 ) }
+            DATA {
+               66, 69, 72, 75, 78, 81,
+               96, 99, 102, 105, 108, 111,
+               126, 129, 132, 135, 138, 141,
+               156, 159, 162, 165, 168, 171,
+               186, 189, 192, 195, 198, 201,
+               216, 219, 222, 225, 228, 231
+            }
+         }
+         DATASET "trefer_reg.h5/Dataset2" {
+            REGION_TYPE POINT  (6,9), (2,2), (8,4), (1,6), (2,8), (3,2),
+             (0,4), (9,0), (7,1), (3,3)
+            DATATYPE  H5T_STD_U8LE
+            DATASPACE  SIMPLE { ( 10, 10 ) / ( 10, 10 ) }
+            DATA {
+               207,
+               66,
+               252,
+               48,
+               84,
+               96,
+               12,
+               14,
+               213,
+               99
+            }
+         }
+         DATASET "trefer_reg.h5/Dataset2"
+         DATASET "trefer_reg.h5/Dataset2"
+      }
+   }
+   DATASET "Dataset2" {
+      DATATYPE  H5T_STD_U8LE
+      DATASPACE  SIMPLE { ( 10, 10 ) / ( 10, 10 ) }
+      DATA {
+      (0,0): 0, 3, 6, 9, 12, 15, 18, 21, 24, 27,
+      (1,0): 30, 33, 36, 39, 42, 45, 48, 51, 54, 57,
+      (2,0): 60, 63, 66, 69, 72, 75, 78, 81, 84, 87,
+      (3,0): 90, 93, 96, 99, 102, 105, 108, 111, 114, 117,
+      (4,0): 120, 123, 126, 129, 132, 135, 138, 141, 144, 147,
+      (5,0): 150, 153, 156, 159, 162, 165, 168, 171, 174, 177,
+      (6,0): 180, 183, 186, 189, 192, 195, 198, 201, 204, 207,
+      (7,0): 210, 213, 216, 219, 222, 225, 228, 231, 234, 237,
+      (8,0): 240, 243, 246, 249, 252, 255, 2, 5, 8, 11,
+      (9,0): 14, 17, 20, 23, 26, 29, 32, 35, 38, 41
+      }
+   }
+}
+}
diff --git a/tools/testfiles/trefer_reg_1d.h5 b/tools/testfiles/trefer_reg_1d.h5
new file mode 100644
index 0000000..932454d
--- /dev/null
+++ b/tools/testfiles/trefer_reg_1d.h5
diff --git a/tools/testfiles/trefer_reg_1dR.ddl b/tools/testfiles/trefer_reg_1dR.ddl
new file mode 100644
index 0000000..3e5f652
--- /dev/null
+++ b/tools/testfiles/trefer_reg_1dR.ddl
@@ -0,0 +1,66 @@
+HDF5 "trefer_reg_1d.h5" {
+GROUP "/" {
+   DATASET "Dataset1" {
+      DATATYPE  H5T_REFERENCE { H5T_STD_REF }
+      DATASPACE  SIMPLE { ( 2 ) / ( 2 ) }
+      DATA {
+         DATASET "trefer_reg_1d.h5/Dataset2" {
+            REGION_TYPE BLOCK  (2)-(3), (7)-(8), (12)-(13), (17)-(18),
+             (22)-(23), (27)-(28), (32)-(33), (37)-(38), (42)-(43),
+             (47)-(48), (52)-(53), (57)-(58), (62)-(63), (67)-(68),
+             (72)-(73)
+            DATATYPE  H5T_STD_U8LE
+            DATASPACE  SIMPLE { ( 100 ) / ( 100 ) }
+            DATA {
+               6, 9,
+               21, 24,
+               36, 39,
+               51, 54,
+               66, 69,
+               81, 84,
+               96, 99,
+               111, 114,
+               126, 129,
+               141, 144,
+               156, 159,
+               171, 174,
+               186, 189,
+               201, 204,
+               216, 219
+            }
+         }
+         DATASET "trefer_reg_1d.h5/Dataset2" {
+            REGION_TYPE POINT  (16), (22), (38), (41), (52), (63), (70),
+             (89), (97), (3)
+            DATATYPE  H5T_STD_U8LE
+            DATASPACE  SIMPLE { ( 100 ) / ( 100 ) }
+            DATA {
+               48,
+               66,
+               114,
+               123,
+               156,
+               189,
+               210,
+               11,
+               35,
+               9
+            }
+         }
+      }
+   }
+   DATASET "Dataset2" {
+      DATATYPE  H5T_STD_U8LE
+      DATASPACE  SIMPLE { ( 100 ) / ( 100 ) }
+      DATA {
+      (0): 0, 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, 42, 45, 48,
+      (17): 51, 54, 57, 60, 63, 66, 69, 72, 75, 78, 81, 84, 87, 90, 93, 96,
+      (33): 99, 102, 105, 108, 111, 114, 117, 120, 123, 126, 129, 132, 135,
+      (46): 138, 141, 144, 147, 150, 153, 156, 159, 162, 165, 168, 171, 174,
+      (59): 177, 180, 183, 186, 189, 192, 195, 198, 201, 204, 207, 210, 213,
+      (72): 216, 219, 222, 225, 228, 231, 234, 237, 240, 243, 246, 249, 252,
+      (85): 255, 2, 5, 8, 11, 14, 17, 20, 23, 26, 29, 32, 35, 38, 41
+      }
+   }
+}
+}