Add EmitWarningsOnPlaceholders calls to contrib modules that are likely to

get listed in custom_variable_classes.

contrib/auto_explain/auto_explain.c

@@ -6,7 +6,7 @@
  * Copyright (c) 2008-2009, PostgreSQL Global Development Group
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/contrib/auto_explain/auto_explain.c,v 1.3 2009/01/02 01:16:02 tgl Exp $
+ *	  $PostgreSQL: pgsql/contrib/auto_explain/auto_explain.c,v 1.4 2009/01/05 13:35:38 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -94,6 +94,8 @@ _PG_init(void)
 							 NULL,
 							 NULL);
 
+	EmitWarningsOnPlaceholders("auto_explain");
+
 	/* Install hooks. */
 	prev_ExecutorStart = ExecutorStart_hook;
 	ExecutorStart_hook = explain_ExecutorStart;

contrib/pg_stat_statements/pg_stat_statements.c

@@ -14,7 +14,7 @@
  * Copyright (c) 2008-2009, PostgreSQL Global Development Group
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/contrib/pg_stat_statements/pg_stat_statements.c,v 1.1 2009/01/04 22:19:59 tgl Exp $
+ *	  $PostgreSQL: pgsql/contrib/pg_stat_statements/pg_stat_statements.c,v 1.2 2009/01/05 13:35:38 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -222,6 +222,8 @@ _PG_init(void)
 							 NULL,
 							 NULL);
 
+	EmitWarningsOnPlaceholders("pg_stat_statements");
+
 	/*
 	 * Request additional shared resources.  (These are no-ops if we're not in
 	 * the postmaster process.)  We'll allocate or attach to the shared