opal/datatype: do not set optimized description if unused

Thanks George for the guidance Refs #3438 Signed-off-by: Gilles Gouaillardet <gilles@rist.or.jp>

Author: ggouaillardet

opal/datatype/opal_datatype_clone.c

@@ -12,6 +12,8 @@
  * All rights reserved.
  * Copyright (c) 2009 Sun Microsystems, Inc. All rights reserved.
  * Copyright (c) 2009 Oak Ridge National Labs. All rights reserved.
+ * Copyright (c) 2017 Research Organization for Information Science
+ * and Technology (RIST). All rights reserved.
  * $COPYRIGHT$
  *
  * Additional copyrights may follow
@@ -61,6 +63,8 @@ int32_t opal_datatype_clone( const opal_datatype_t * src_type, opal_datatype_t *
  dest_type->opt_desc.used = src_type->opt_desc.used;
  memcpy( dest_type->opt_desc.desc, src_type->opt_desc.desc, desc_length * sizeof(dt_elem_desc_t) );
  }
+ } else {
+ assert(NULL == dest_type->opt_desc.desc);
  }
  }
  dest_type->id = src_type->id; /* preserve the default id. This allow us to

opal/datatype/opal_datatype_optimize.c

@@ -247,6 +247,12 @@ opal_datatype_optimize_short( opal_datatype_t* pData,
  }
  /* cleanup the stack */
  pTypeDesc->used = nbElems - 1; /* except the last fake END_LOOP */
+ if (OPAL_UNLIKELY(0 == pTypeDesc->used)) {
+ /* optimized description is not gonna be used, so free it */
+ free(pTypeDesc->desc);
+ pTypeDesc->desc = NULL;
+ pTypeDesc->length = 0;
+ }
  free(pOrigStack);
  return OPAL_SUCCESS;
 }