From 63e98b55f04004423852fa1e1730761074c412db Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Mon, 19 May 2008 04:14:24 +0000
Subject: [PATCH] Coercion sanity check in ri_HashCompareOp failed to allow for
 enums, as per example from Rod Taylor.  On reflection the correct test here
 is for any polymorphic type, not specifically ANYARRAY as in the original
 coding.

---
 src/backend/commands/tablecmds.c    | 12 ++++++------
 src/backend/utils/adt/ri_triggers.c | 10 +++++++---
 2 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 0bef48e07b..58f0b01b09 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.254 2008/05/16 23:36:04 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.255 2008/05/19 04:14:24 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -4377,11 +4377,11 @@ ATAddForeignKeyConstraint(AlteredTableInfo *tab, Relation rel,
 			/*
 			 * Otherwise, look for an implicit cast from the FK type to the
 			 * opcintype, and if found, use the primary equality operator.
-			 * This is a bit tricky because opcintype might be a generic type
-			 * such as ANYARRAY, and so what we have to test is whether the
-			 * two actual column types can be concurrently cast to that type.
-			 * (Otherwise, we'd fail to reject combinations such as int[] and
-			 * point[].)
+			 * This is a bit tricky because opcintype might be a polymorphic
+			 * type such as ANYARRAY or ANYENUM; so what we have to test is
+			 * whether the two actual column types can be concurrently cast to
+			 * that type.  (Otherwise, we'd fail to reject combinations such
+			 * as int[] and point[].)
 			 */
 			Oid			input_typeids[2];
 			Oid			target_typeids[2];
diff --git a/src/backend/utils/adt/ri_triggers.c b/src/backend/utils/adt/ri_triggers.c
index 59f7e49795..7f564e09fa 100644
--- a/src/backend/utils/adt/ri_triggers.c
+++ b/src/backend/utils/adt/ri_triggers.c
@@ -15,7 +15,7 @@
  *
  * Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
  *
- * $PostgreSQL: pgsql/src/backend/utils/adt/ri_triggers.c,v 1.108 2008/05/12 20:02:02 alvherre Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/adt/ri_triggers.c,v 1.109 2008/05/19 04:14:24 tgl Exp $
  *
  * ----------
  */
@@ -3938,8 +3938,12 @@ ri_HashCompareOp(Oid eq_opr, Oid typeid)
 			if (pathtype != COERCION_PATH_FUNC &&
 				pathtype != COERCION_PATH_RELABELTYPE)
 			{
-				/* If target is ANYARRAY, assume it's OK, else punt. */
-				if (lefttype != ANYARRAYOID)
+				/*
+				 * The declared input type of the eq_opr might be a
+				 * polymorphic type such as ANYARRAY or ANYENUM.  If so,
+				 * assume the coercion is valid; otherwise complain.
+				 */
+				if (!IsPolymorphicType(lefttype))
 					elog(ERROR, "no conversion function from %s to %s",
 						 format_type_be(typeid),
 						 format_type_be(lefttype));