diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c
index 6c0c53d0748..2cfa43caf9a 100644
--- a/src/backend/parser/parse_expr.c
+++ b/src/backend/parser/parse_expr.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_expr.c,v 1.163.2.3 2005/05/25 02:13:48 ishii Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_expr.c,v 1.163.2.4 2005/11/18 23:08:43 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1425,8 +1425,12 @@ exprTypmod(Node *expr)
 				int32		typmod;
 				List	   *arg;
 
+				if (exprType((Node *) lfirst(cexpr->args)) != coalescetype)
+					return -1;
 				typmod = exprTypmod((Node *) lfirst(cexpr->args));
-				foreach(arg, cexpr->args)
+				if (typmod < 0)
+					return -1;	/* no point in trying harder */
+				foreach(arg, lnext(cexpr->args))
 				{
 					Node	   *e = (Node *) lfirst(arg);