Much normalization with develop (#701)

* Brings CMake updates from develop

* Brings reduction in pedantic casts from develop

* Purges UFAIL from the library (#637)

* Committing clang-format changes

* Purges UFAIL from the library

* H5HL_insert change requested in PR

Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>

* Removes gratuitous (double)x.yF casts (#632)

* Committing clang-format changes

* Removes gratuitous (double)x.yF casts

* Committing clang-format changes

Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>

* Committing clang-format changes

* Cleans up a const warning left over from previous constification (#633)

* Committing clang-format changes

* Adds consts to a few global variables

* Cleans up a const warning left over from previous constification

Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>

* Formatted source

* Bring over some VOL registration changes

* VOL cleanup

* H5VL_request_status_t substitutions

* H5F.c cleanup

* Minor API tweaks from develop

* Moves H5G package init/teardown to H5Gint.c

* H5G cleanup

* H5M cleanup

* H5SM cleanup

* H5T cleanup

* H5R cleanup

* H5Lpublic.h cleanup

* H5L cleanup

* H5O cleanup

* H5A, H5CS, and H5AC cleanup

* Moved H5A init/teardown code to H5Aint.c

* Moves H5D I/O functions to H5D.c

* H5D cleanup

* Misc minor cleanup

* H5P close cleanup

* H5Tpublic.h cleanup

* Fixes err_compat test

* H5PLpublic.h cleanup

* Updates H5Ppublic.h

* H5Fpublic.h updates

* H5A.c cleanup

* Brings over H5Aexists and related changes

* Brings CMake shell testing changes from develop

* Close callback changes

* H5R and H5Tcommit normalization

* err_compat test works now

* H5O tweaks

* Updates VOL registration code

* Brings over H5VL_create_object

* H5Tconv.c reformatting

* H5T.c tweaks

* Brings datatype and reference updates from develop

* Brings VOL plugin loading changes from develop

* Brings event sets from develop

* Brings async functions over

* Tools changes

* Brings over many tools changes from develop

* Brings VOL flags from develop

* Fixes h5dump double/float tests

* Updates h5repack tests

* Brings h5diff test changes from develop

* Last h5dump changes

* Brings test changes from develop

* Committing clang-format changes

* Tidied h5_testing()

* Brings chunk iteration code + misc from develop

* Updates vds test

* Enables external link parallel test

* Brings updated property lists from develop

* H5G changes from develop

* H5MF cleanup

* Brings vfd_swmr test back into CMake

* Updates threadsafe test

* Updates plist test

* Brings recent changes from develop

Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>

1 files changed, 217 insertions, 67 deletions

diff --git a/src/H5Tcommit.c b/src/H5Tcommit.c
index 0842312..d214ca1 100644
--- a/src/H5Tcommit.c
+++ b/src/H5Tcommit.c
@@ -29,6 +29,7 @@
 #include "H5ACprivate.h" /* Metadata cache                           */
 #include "H5CXprivate.h" /* API Contexts                             */
 #include "H5Eprivate.h"  /* Error handling                           */
+#include "H5ESprivate.h" /* Event Sets                               */
 #include "H5FLprivate.h" /* Free lists                               */
 #include "H5FOprivate.h" /* File objects                             */
 #include "H5Iprivate.h"  /* IDs                                      */
@@ -54,6 +55,11 @@
 /********************/
 /* Local Prototypes */
 /********************/
+static herr_t H5T__commit_api_common(hid_t loc_id, const char *name, hid_t type_id, hid_t lcpl_id,
+                                     hid_t tcpl_id, hid_t tapl_id, void **token_ptr,
+                                     H5VL_object_t **_vol_obj_ptr);
+static hid_t  H5T__open_api_common(hid_t loc_id, const char *name, hid_t tapl_id, void **token_ptr,
+                                   H5VL_object_t **_vol_obj_ptr);
 static H5T_t *H5T__open_oid(const H5G_loc_t *loc);
 
 /*********************/
@@ -79,27 +85,28 @@ H5FL_EXTERN(H5VL_t);
 H5FL_EXTERN(H5VL_object_t);
 
 /*-------------------------------------------------------------------------
- * Function:    H5Tcommit2
+ * Function:    H5T__commit_api_common
  *
- * Purpose:     Save a transient datatype to a file and turn the type handle
- *              into a "named", immutable type.
+ * Purpose:     This is the common function for committing a datytype.
  *
- * Return:      SUCCEED/FAIL
+ * Return:      Non-negative on success/Negative on failure
  *
  *-------------------------------------------------------------------------
  */
-herr_t
-H5Tcommit2(hid_t loc_id, const char *name, hid_t type_id, hid_t lcpl_id, hid_t tcpl_id, hid_t tapl_id)
+static herr_t
+H5T__commit_api_common(hid_t loc_id, const char *name, hid_t type_id, hid_t lcpl_id, hid_t tcpl_id,
+                       hid_t tapl_id, void **token_ptr, H5VL_object_t **_vol_obj_ptr)
 {
-    void *            data    = NULL; /* VOL-managed datatype data */
-    H5VL_object_t *   new_obj = NULL; /* VOL object that holds the datatype object and the VOL info */
-    H5T_t *           dt      = NULL; /* High level datatype object that wraps the VOL object */
-    H5VL_object_t *   vol_obj = NULL; /* object of loc_id */
-    H5VL_loc_params_t loc_params;
-    herr_t            ret_value = SUCCEED; /* Return value */
+    void *          data        = NULL; /* VOL-managed datatype data */
+    H5VL_object_t * new_obj     = NULL; /* VOL object that holds the datatype object and the VOL info */
+    H5T_t *         dt          = NULL; /* High level datatype object that wraps the VOL object */
+    H5VL_object_t * tmp_vol_obj = NULL; /* Object for loc_id */
+    H5VL_object_t **vol_obj_ptr =
+        (_vol_obj_ptr ? _vol_obj_ptr : &tmp_vol_obj); /* Ptr to object ptr for loc_id */
+    H5VL_loc_params_t loc_params;                     /* Location parameters */
+    herr_t            ret_value = SUCCEED;            /* Return value */
 
-    FUNC_ENTER_API(FAIL)
-    H5TRACE6("e", "i*siiii", loc_id, name, type_id, lcpl_id, tcpl_id, tapl_id);
+    FUNC_ENTER_STATIC
 
     /* Check arguments */
     if (!name)
@@ -126,38 +133,100 @@ H5Tcommit2(hid_t loc_id, const char *name, hid_t type_id, hid_t lcpl_id, hid_t t
     /* Set the LCPL for the API context */
     H5CX_set_lcpl(lcpl_id);
 
-    /* Verify access property list and set up collective metadata if appropriate */
-    if (H5CX_set_apl(&tapl_id, H5P_CLS_TACC, loc_id, TRUE) < 0)
-        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTSET, FAIL, "can't set access property list info")
-
-    /* Fill in location struct fields */
-    loc_params.type     = H5VL_OBJECT_BY_SELF;
-    loc_params.obj_type = H5I_get_type(loc_id);
-
-    /* Get the object from the loc_id */
-    if (NULL == (vol_obj = (H5VL_object_t *)H5I_object(loc_id)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid object identifier")
+    /* Set up object access arguments */
+    if (H5VL_setup_acc_args(loc_id, H5P_CLS_TACC, TRUE, &tapl_id, vol_obj_ptr, &loc_params) < 0)
+        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTSET, FAIL, "can't set object access arguments")
 
     /* Commit the type */
-    if (NULL == (data = H5VL_datatype_commit(vol_obj, &loc_params, name, type_id, lcpl_id, tcpl_id, tapl_id,
-                                             H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL)))
+    if (NULL == (data = H5VL_datatype_commit(*vol_obj_ptr, &loc_params, name, type_id, lcpl_id, tcpl_id,
+                                             tapl_id, H5P_DATASET_XFER_DEFAULT, token_ptr)))
         HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "unable to commit datatype")
 
     /* Set up VOL object */
-    if (NULL == (new_obj = H5FL_CALLOC(H5VL_object_t)))
-        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTALLOC, FAIL, "can't allocate top object structure")
-    new_obj->connector = vol_obj->connector;
-    new_obj->connector->nrefs++;
-    new_obj->data = data;
+    if (NULL == (new_obj = H5VL_create_object(data, (*vol_obj_ptr)->connector)))
+        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTALLOC, FAIL, "can't create VOL object for committed datatype")
 
     /* Set the committed type object to the VOL connector pointer in the H5T_t struct */
     dt->vol_obj = new_obj;
 
 done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5T__commit_api_common() */
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Tcommit2
+ *
+ * Purpose:     Save a transient datatype to a file and turn the type handle
+ *              into a "named", immutable type.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Quincey Koziol
+ *              April 5, 2007
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Tcommit2(hid_t loc_id, const char *name, hid_t type_id, hid_t lcpl_id, hid_t tcpl_id, hid_t tapl_id)
+{
+    herr_t ret_value = SUCCEED; /* Return value */
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE6("e", "i*siiii", loc_id, name, type_id, lcpl_id, tcpl_id, tapl_id);
+
+    /* Commit the dataset synchronously */
+    if ((ret_value = H5T__commit_api_common(loc_id, name, type_id, lcpl_id, tcpl_id, tapl_id, NULL, NULL)) <
+        0)
+        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTOPENOBJ, FAIL, "unable to commit datatype synchronously")
+
+done:
     FUNC_LEAVE_API(ret_value)
 } /* end H5Tcommit2() */
 
 /*-------------------------------------------------------------------------
+ * Function:    H5Tcommit_async
+ *
+ * Purpose:     Asynchronous version of H5Tcommit2
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Tcommit_async(const char *app_file, const char *app_func, unsigned app_line, hid_t loc_id, const char *name,
+                hid_t type_id, hid_t lcpl_id, hid_t tcpl_id, hid_t tapl_id, hid_t es_id)
+{
+    H5VL_object_t *vol_obj   = NULL;            /* Object for loc_id */
+    void *         token     = NULL;            /* Request token for async operation        */
+    void **        token_ptr = H5_REQUEST_NULL; /* Pointer to request token for async operation        */
+    herr_t         ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE10("e", "*s*sIui*siiiii", app_file, app_func, app_line, loc_id, name, type_id, lcpl_id, tcpl_id,
+              tapl_id, es_id);
+
+    /* Set up request token pointer for asynchronous operation */
+    if (H5ES_NONE != es_id)
+        token_ptr = &token;
+
+    /* Commit the datatype asynchronously */
+    if ((ret_value = H5T__commit_api_common(loc_id, name, type_id, lcpl_id, tcpl_id, tapl_id, token_ptr,
+                                            &vol_obj)) < 0)
+        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTOPENOBJ, FAIL, "unable to commit datatype asynchronously")
+
+    /* If a token was created, add the token to the event set */
+    if (NULL != token)
+        /* clang-format off */
+        if (H5ES_insert(es_id, vol_obj->connector, token,
+                        H5ARG_TRACE10(FUNC, "*s*sIui*siiiii", app_file, app_func, app_line, loc_id, name, type_id, lcpl_id, tcpl_id, tapl_id, es_id)) < 0)
+            /* clang-format on */
+            HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINSERT, FAIL, "can't insert token into event set")
+
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* end H5Tcommit_async() */
+
+/*-------------------------------------------------------------------------
  * Function:	H5T__commit_named
  *
  * Purpose:	Internal routine to save a transient datatype to a file and
@@ -248,7 +317,10 @@ done:
  * Note:        The datatype access property list is unused currently, but
  *              is checked for sanity anyway.
  *
- * Return:      SUCCEED/FAIL
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Peter Cao
+ *              May 17, 2005
  *
  *-------------------------------------------------------------------------
  */
@@ -295,11 +367,8 @@ H5Tcommit_anon(hid_t loc_id, hid_t type_id, hid_t tcpl_id, hid_t tapl_id)
         HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "unable to commit datatype")
 
     /* Setup VOL object */
-    if (NULL == (new_obj = H5FL_CALLOC(H5VL_object_t)))
-        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTALLOC, FAIL, "can't allocate top object structure")
-    new_obj->connector = vol_obj->connector;
-    new_obj->connector->nrefs++;
-    new_obj->data = dt;
+    if (NULL == (new_obj = H5VL_create_object(dt, vol_obj->connector)))
+        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTALLOC, FAIL, "can't create VOL object for committed datatype")
 
     /* Set the committed type object to the VOL connector pointer in the H5T_t struct */
     type->vol_obj = new_obj;
@@ -479,7 +548,10 @@ done:
  *
  * Purpose:     Determines if a datatype is committed or not.
  *
- * Return:      TRUE/FALSE/FAIL
+ * Return:      TRUE/FALSE/Negative
+ *
+ * Programmer:	Robb Matzke
+ *              Thursday, June  4, 1998
  *
  *-------------------------------------------------------------------------
  */
@@ -510,7 +582,7 @@ done:
  *		ADJUST to the link count.
  *
  * Return:	Success:	New link count
- *		Failure:	Negative
+ *		Failure:	-1
  *
  * Programmer:	Quincey Koziol
  *              Friday, September 26, 2003
@@ -536,10 +608,9 @@ done:
 } /* end H5T_link() */
 
 /*-------------------------------------------------------------------------
- * Function:    H5Topen2
+ * Function:    H5T__open_api_common
  *
- * Purpose:     Opens a named datatype using a Datatype Access Property
- *              List.
+ * Purpose:     This is the common function for opening a datatype.
  *
  * Return:      Success:    Object ID of the named datatype
  *
@@ -547,16 +618,18 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-hid_t
-H5Topen2(hid_t loc_id, const char *name, hid_t tapl_id)
+static hid_t
+H5T__open_api_common(hid_t loc_id, const char *name, hid_t tapl_id, void **token_ptr,
+                     H5VL_object_t **_vol_obj_ptr)
 {
-    void *            dt      = NULL; /* datatype object created by VOL connector */
-    H5VL_object_t *   vol_obj = NULL; /* object of loc_id */
+    void *          dt          = NULL; /* datatype object created by VOL connector */
+    H5VL_object_t * tmp_vol_obj = NULL; /* Object for loc_id */
+    H5VL_object_t **vol_obj_ptr =
+        (_vol_obj_ptr ? _vol_obj_ptr : &tmp_vol_obj); /* Ptr to object ptr for loc_id */
     H5VL_loc_params_t loc_params;
     hid_t             ret_value = H5I_INVALID_HID; /* Return value */
 
-    FUNC_ENTER_API(H5I_INVALID_HID)
-    H5TRACE3("i", "i*si", loc_id, name, tapl_id);
+    FUNC_ENTER_STATIC
 
     /* Check args */
     if (!name)
@@ -564,37 +637,108 @@ H5Topen2(hid_t loc_id, const char *name, hid_t tapl_id)
     if (!*name)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, H5I_INVALID_HID, "name parameter cannot be an empty string")
 
-    /* Verify access property list and set up collective metadata if appropriate */
-    if (H5CX_set_apl(&tapl_id, H5P_CLS_TACC, loc_id, FALSE) < 0)
-        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTSET, FAIL, "can't set access property list info")
-
-    /* Fill in location struct fields */
-    loc_params.type     = H5VL_OBJECT_BY_SELF;
-    loc_params.obj_type = H5I_get_type(loc_id);
-
-    /* get the location object */
-    if (NULL == (vol_obj = (H5VL_object_t *)H5I_object(loc_id)))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5I_INVALID_HID, "invalid file identifier")
+    /* Set up object access arguments */
+    if (H5VL_setup_acc_args(loc_id, H5P_CLS_TACC, FALSE, &tapl_id, vol_obj_ptr, &loc_params) < 0)
+        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTSET, H5I_INVALID_HID, "can't set object access arguments")
 
     /* Open the datatype */
-    if (NULL == (dt = H5VL_datatype_open(vol_obj, &loc_params, name, tapl_id, H5P_DATASET_XFER_DEFAULT,
-                                         H5_REQUEST_NULL)))
+    if (NULL == (dt = H5VL_datatype_open(*vol_obj_ptr, &loc_params, name, tapl_id, H5P_DATASET_XFER_DEFAULT,
+                                         token_ptr)))
         HGOTO_ERROR(H5E_DATATYPE, H5E_CANTOPENOBJ, H5I_INVALID_HID, "unable to open named datatype")
 
     /* Register the type and return the ID */
-    if ((ret_value = H5VL_register(H5I_DATATYPE, dt, vol_obj->connector, TRUE)) < 0)
+    if ((ret_value = H5VL_register(H5I_DATATYPE, dt, (*vol_obj_ptr)->connector, TRUE)) < 0)
         HGOTO_ERROR(H5E_DATATYPE, H5E_CANTREGISTER, H5I_INVALID_HID, "unable to register named datatype")
 
 done:
     /* Cleanup on error */
     if (H5I_INVALID_HID == ret_value)
-        if (dt && H5VL_datatype_close(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
+        if (dt && H5VL_datatype_close(*vol_obj_ptr, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL) < 0)
             HDONE_ERROR(H5E_DATATYPE, H5E_CLOSEERROR, H5I_INVALID_HID, "unable to release datatype")
 
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5T__open_api_common() */
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Topen2
+ *
+ * Purpose:     Opens a named datatype using a Datatype Access Property
+ *              List.
+ *
+ * Return:      Success:    Object ID of the named datatype
+ *
+ *              Failure:    H5I_INVALID_HID
+ *
+ * Programmer:  James Laird
+ *              Thursday July 27, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+hid_t
+H5Topen2(hid_t loc_id, const char *name, hid_t tapl_id)
+{
+    hid_t ret_value = H5I_INVALID_HID; /* Return value */
+
+    FUNC_ENTER_API(H5I_INVALID_HID)
+    H5TRACE3("i", "i*si", loc_id, name, tapl_id);
+
+    /* Open the datatype synchronously */
+    if ((ret_value = H5T__open_api_common(loc_id, name, tapl_id, NULL, NULL)) < 0)
+        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTOPENOBJ, H5I_INVALID_HID,
+                    "unable to open named datatype synchronously")
+done:
     FUNC_LEAVE_API(ret_value)
 } /* end H5Topen2() */
 
 /*-------------------------------------------------------------------------
+ * Function:    H5Topen_async
+ *
+ * Purpose:     Asynchronous version of H5Topen2.
+ *
+ * Return:      Success:    Object ID of the named datatype
+ *
+ *              Failure:    H5I_INVALID_HID
+ *
+ *-------------------------------------------------------------------------
+ */
+hid_t
+H5Topen_async(const char *app_file, const char *app_func, unsigned app_line, hid_t loc_id, const char *name,
+              hid_t tapl_id, hid_t es_id)
+{
+    H5VL_object_t *vol_obj   = NULL;            /* Object for loc_id */
+    void *         token     = NULL;            /* Request token for async operation */
+    void **        token_ptr = H5_REQUEST_NULL; /* Pointer to request token for async operation */
+    hid_t          ret_value = H5I_INVALID_HID; /* Return value */
+
+    FUNC_ENTER_API(H5I_INVALID_HID)
+    H5TRACE7("i", "*s*sIui*sii", app_file, app_func, app_line, loc_id, name, tapl_id, es_id);
+
+    /* Set up request token pointer for asynchronous operation */
+    if (H5ES_NONE != es_id)
+        token_ptr = &token; /* Point at token for VOL connector to set up */
+
+    /* Open the datatype asynchronously */
+    if ((ret_value = H5T__open_api_common(loc_id, name, tapl_id, token_ptr, &vol_obj)) < 0)
+        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTOPENOBJ, H5I_INVALID_HID,
+                    "unable to open named datatype asynchronously")
+
+    /* If a token was created, add the token to the event set */
+    if (NULL != token)
+        /* clang-format off */
+        if (H5ES_insert(es_id, vol_obj->connector, token,
+                        H5ARG_TRACE7(FUNC, "*s*sIui*sii", app_file, app_func, app_line, loc_id, name, tapl_id, es_id)) < 0) {
+            /* clang-format on */
+            if (H5I_dec_app_ref_always_close(ret_value) < 0)
+                HGOTO_ERROR(H5E_DATATYPE, H5E_CANTDEC, H5I_INVALID_HID,
+                            "can't decrement count on datatype ID")
+            HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINSERT, H5I_INVALID_HID, "can't insert token into event set")
+        } /* end if */
+
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* end H5Topen_async() */
+
+/*-------------------------------------------------------------------------
  * Function:    H5Tget_create_plist
  *
  * Purpose:     Returns a copy of the datatype creation property list.
@@ -608,6 +752,9 @@ done:
  *
  *              Failure:    H5I_INVALID_HID
  *
+ * Programmer:	Quincey Koziol
+ *		Tuesday, November 28, 2006
+ *
  *-------------------------------------------------------------------------
  */
 hid_t
@@ -961,8 +1108,11 @@ H5T_open(const H5G_loc_t *loc)
 done:
     if (ret_value == NULL) {
         if (dt) {
-            if (shared_fo == NULL) /* Need to free shared fo */
+            if (shared_fo == NULL) { /* Need to free shared fo */
+                if (dt->shared->owned_vol_obj && H5VL_free_object(dt->shared->owned_vol_obj) < 0)
+                    HDONE_ERROR(H5E_DATATYPE, H5E_CANTCLOSEOBJ, NULL, "unable to close owned VOL object")
                 dt->shared = H5FL_FREE(H5T_shared_t, dt->shared);
+            } /* end if */
 
             H5O_loc_free(&(dt->oloc));
             H5G_name_free(&(dt->path));
@@ -1180,7 +1330,7 @@ H5T_save_refresh_state(hid_t tid, H5O_shared_t *cached_H5O_shared)
 
     if (NULL == (dt = (H5T_t *)H5I_object_verify(tid, H5I_DATATYPE)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "tid is not a datatype ID")
-    vol_dt = (H5T_t *)(dt->vol_obj->data);
+    vol_dt = H5T_get_actual_type(dt);
     if (NULL == vol_dt)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "tid is not not a named datatype ID")
 
@@ -1220,7 +1370,7 @@ H5T_restore_refresh_state(hid_t tid, H5O_shared_t *cached_H5O_shared)
 
     if (NULL == (dt = (H5T_t *)H5I_object_verify(tid, H5I_DATATYPE)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "tid not a datatype ID")
-    vol_dt = (H5T_t *)(dt->vol_obj->data);
+    vol_dt = H5T_get_actual_type(dt);
     if (NULL == vol_dt)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "tid is not not a named datatype ID")