zero_damaged_pages must absolutely NOT be marked GUC_DISALLOW_IN_FILE,

else it cannot be used to handle failures detected during WAL replay.
Fortunately this flag isn't actually enforced yet, but get it right.

src/backend/utils/misc/guc.c

@@ -10,7 +10,7 @@
  * Written by Peter Eisentraut <peter_e@gmx.net>.
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.165 2003/11/06 22:08:15 petere Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.166 2003/11/07 21:27:38 tgl Exp $
  *
  *--------------------------------------------------------------------
  */
@@ -466,7 +466,7 @@ static struct config_bool ConfigureNamesBool[] =
 						 "zero_damaged_pages to true causes the system to instead report a "
 						 "warning, zero out the damaged page, and continue processing. This "
 						 "behavior will destroy data, namely all the rows on the damaged page."),
-			GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE
+			GUC_NOT_IN_SAMPLE
 		},
 		&zero_damaged_pages,
 		false, NULL, NULL