Clean up a few places where Datums were being treated as pointers without

going through DatumGetPointer or some other "official" conversion macro.
Not actually a bug, since Datum the same size as pointer is the only
supported case at the moment, but good cleanup for the future.

Gavin Sherry

src/backend/utils/adt/varlena.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/varlena.c,v 1.164 2008/03/25 22:42:44 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/varlena.c,v 1.165 2008/04/12 23:21:04 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -754,7 +754,8 @@ text_substring(Datum str, int32 start, int32 length, bool length_not_specified)
 		 * If we're working with an untoasted source, no need to do an extra
 		 * copying step.
 		 */
-		if (VARATT_IS_COMPRESSED(str) || VARATT_IS_EXTERNAL(str))
+		if (VARATT_IS_COMPRESSED(DatumGetPointer(str)) || 
+			VARATT_IS_EXTERNAL(DatumGetPointer(str)))
 			slice = DatumGetTextPSlice(str, slice_start, slice_size);
 		else
 			slice = (text *) DatumGetPointer(str);

src/backend/utils/mb/mbutils.c

@@ -4,7 +4,7 @@
  * (currently mule internal code (mic) is used)
  * Tatsuo Ishii
  *
- * $PostgreSQL: pgsql/src/backend/utils/mb/mbutils.c,v 1.69 2008/01/09 23:43:54 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/mb/mbutils.c,v 1.70 2008/04/12 23:21:04 tgl Exp $
  */
 #include "postgres.h"
 
@@ -313,7 +313,7 @@ pg_convert_to(PG_FUNCTION_ARGS)
 	result = DirectFunctionCall3(pg_convert, string,
 								 src_encoding_name, dest_encoding_name);
 
-	PG_RETURN_BYTEA_P(result);
+	PG_RETURN_DATUM(result);
 }
 
 /*
@@ -340,7 +340,7 @@ pg_convert_from(PG_FUNCTION_ARGS)
 	 * in this case it will be because we've told pg_convert to return one
 	 * that is valid as text in the current database encoding.
 	 */
-	PG_RETURN_TEXT_P(result);
+	PG_RETURN_DATUM(result);
 }
 
 /*