(fix) Segmentation fault when using a compound type.

MANIFEST

@@ -1096,6 +1096,7 @@
 ./test/cache_tagging.c
 ./test/chunk_info.c
 ./test/cmpd_dset.c
+./test/cmpd_dtransform.c
 ./test/cork.c
 ./test/corrupt_stab_msg.h5
 ./test/cross_read.c

src/H5T.c

@@ -3405,8 +3405,8 @@ H5T__create(H5T_class_t type, size_t size)
  * Note:      Common code for both H5T_copy and H5T_copy_reopen, as part of
  *            the const-correct datatype copying routines.
  *
- * Programmer:	David Young
- *	        January 18, 2020
+ * Programmer:  David Young
+ *              January 18, 2020
  *
  *-------------------------------------------------------------------------
  */
@@ -3453,8 +3453,8 @@ H5T__initiate_copy(const H5T_t *old_dt)
  * Return:    Success:    Pointer to a new copy of the OLD_DT argument.
  *            Failure:    NULL
  *
- * Programmer:	David Young
- *	        January 18, 2020
+ * Programmer:  David Young
+ *              January 18, 2020
  *
  *-------------------------------------------------------------------------
  */
@@ -3481,8 +3481,8 @@ H5T__copy_transient(H5T_t *old_dt)
  * Return:    Success:    Pointer to a new copy of the OLD_DT argument.
  *            Failure:    NULL
  *
- * Programmer:	David Young
- *	        January 18, 2020
+ * Programmer:  David Young
+ *              January 18, 2020
  *
  *-------------------------------------------------------------------------
  */
@@ -3512,8 +3512,8 @@ H5T__copy_all(H5T_t *old_dt)
  *
  * Note:      Common code for both H5T_copy and H5T_copy_reopen.
  *
- * Programmer:	David Young
- *	        January 18, 2020
+ * Programmer:  David Young
+ *              January 18, 2020
  *
  *-------------------------------------------------------------------------
  */
@@ -3783,8 +3783,8 @@ H5T_copy(const H5T_t *old_dt, H5T_copy_t method)
  * Return:    Success:    Pointer to a new copy of the OLD_DT argument.
  *            Failure:    NULL
  *
- * Programmer:	David Young
- *	        January 18, 2020
+ * Programmer:  David Young
+ *              January 18, 2020
  *
  *-------------------------------------------------------------------------
  */
@@ -5217,7 +5217,10 @@ H5T__path_find_real(const H5T_t *src, const H5T_t *dst, const char *name, H5T_co
     } /* end else-if */
 
     /* Set the flag to indicate both source and destination types are compound types
-     * for the optimization of data reading (in H5Dio.c). */
+     * for the optimization of data reading (in H5Dio.c).
+     * Make sure that path->are_compounds is only TRUE for compound types.
+     */
+    path->are_compounds = FALSE;
     if (H5T_COMPOUND == H5T_get_class(src, TRUE) && H5T_COMPOUND == H5T_get_class(dst, TRUE))
         path->are_compounds = TRUE;
 

test/CMakeLists.txt

@@ -332,6 +332,7 @@ set (H5_TESTS
     thread_id # special link
     vol
     timer
+    cmpd_dtransform
 )
 
 macro (ADD_H5_EXE file)

test/cmpd_dtransform.c

@@ -0,0 +1,139 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by The HDF Group.                                               *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * All rights reserved.                                                      *
+ *                                                                           *
+ * This file is part of HDF5.  The full HDF5 copyright notice, including     *
+ * terms governing use, modification, and redistribution, is contained in    *
+ * the files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic HDF5 document set and   *
+ * is linked from the top-level documents page.  It can also be found at     *
+ * http://hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have          *
+ * access to either file, you may request a copy from help@hdfgroup.org.     *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*
+ * Programmer:  Jan-Willem Blokland
+ *              December 1, 2020
+ *
+ * Purpose:     Test writing compounded attribute followed by
+ *              writing data with a data transform functiun.
+ */
+
+#include "h5test.h"
+
+#define FILENAME "cmpd_dtransform.h5"
+#define LENGTH   11
+
+typedef struct {
+  char name[64];
+  char unit[64];
+} att_t;
+
+int
+main(void)
+{
+    hsize_t  dima[] = { 1 };
+    hsize_t  dims[] = { LENGTH };
+    hid_t    str_dtyp_id, att_dtyp_id, file_id, fspace_id, dset_id, att_dspc_id, att_attr_id, dxpl_id;
+
+    /* Compound datatype */
+    att_t *atts = HDmalloc(sizeof(att_t));
+    HDstrcpy(atts[0].name, "Name");
+    HDstrcpy(atts[0].unit, "Unit");
+
+    /* String type */
+    if ((str_dtyp_id = H5Tcopy(H5T_C_S1)) < 0)
+      TEST_ERROR;
+    H5Tset_size(str_dtyp_id, 64);
+
+    /* Attribute type */
+    if ((att_dtyp_id = H5Tcreate(H5T_COMPOUND, sizeof(att_t))) < 0)
+      TEST_ERROR;
+    H5Tinsert(att_dtyp_id, "NAME", HOFFSET(att_t, name), str_dtyp_id);
+    H5Tinsert(att_dtyp_id, "UNIT", HOFFSET(att_t, unit), str_dtyp_id);
+
+    /* Create file. */
+    if ((file_id = H5Fcreate(FILENAME, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT)) < 0)
+      TEST_ERROR;
+
+    /* Create file dataspace. */
+    if ((fspace_id = H5Screate_simple(1, dims, NULL)) < 0)
+      TEST_ERROR;
+
+    /* Create dataset. */
+    if ((dset_id = H5Dcreate2(file_id, "test_dset", H5T_NATIVE_INT, fspace_id, 
+                              H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0)
+      TEST_ERROR;
+
+    /* Write the attribute (compound) to the dataset */
+    if ((att_dspc_id = H5Screate_simple(1, dima, NULL)) < 0)
+      TEST_ERROR;
+    if ((att_attr_id = H5Acreate2(dset_id, "ATTRIBUTES", att_dtyp_id, att_dspc_id, 
+                                  H5P_DEFAULT, H5P_DEFAULT)) < 0)
+      TEST_ERROR;
+    if (H5Awrite(att_attr_id, att_dtyp_id, atts) < 0)
+      TEST_ERROR;
+
+    /* Create dataset transfer property list */
+    const char *expr = "2*x";
+    if ((dxpl_id = H5Pcreate(H5P_DATASET_XFER)) < 0)
+      TEST_ERROR;
+    if (H5Pset_data_transform(dxpl_id, expr) < 0) {
+      HDprintf("**** ERROR: H5Pset_data_transform (expression: %s) ****\n", expr);
+      TEST_ERROR;
+    }
+
+    int *data     = HDmalloc(LENGTH * sizeof(int));
+    int *data_res = HDmalloc(LENGTH * sizeof(int));
+    for (unsigned i = 0; i < LENGTH; i++) {
+      data[i]     = 10;
+      data_res[i] = 2 * data[i];
+    }
+
+    /* Write the data */
+    if (H5Dwrite(dset_id, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, dxpl_id, data) < 0)
+      TEST_ERROR;
+
+    /* Read attribute */
+    att_t *atts_res  =HDmalloc(sizeof(att_t));
+    if (H5Aread(att_attr_id, att_dtyp_id, atts_res) < 0)
+      TEST_ERROR;
+
+    /* Verify attribute */
+    if (HDstrcmp(atts_res[0].name, atts[0].name) != 0)
+      TEST_ERROR;
+    if (HDstrcmp(atts_res[0].unit, atts[0].unit) != 0)
+      TEST_ERROR;
+
+    /* Read the data */
+    if (H5Dread(dset_id, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, data) < 0)
+      TEST_ERROR;
+
+    /* Verify data */
+    for (unsigned idx = 0; idx < LENGTH; idx++) {
+      if (data[idx] != data_res[idx])
+        TEST_ERROR;
+    }
+
+    HDfree(atts);
+    HDfree(atts_res);
+    HDfree(data);
+    HDfree(data_res);
+
+    /* Close all identifiers. */
+    H5Pclose(dxpl_id);
+    H5Aclose(att_attr_id);
+    H5Sclose(att_dspc_id);
+    H5Dclose(dset_id);
+    H5Sclose(fspace_id);
+    H5Fclose(file_id);
+    H5Tclose(att_dtyp_id);
+    H5Tclose(str_dtyp_id);
+
+    return 0;
+
+ error:
+    return 1;
+}