Modify raw parsetree representation returned by gram.y for SubLinks:

the oper field should be a valid Node structure so it can be dumped by
outfuncs.c without risk of coredump.  (We had been using a raw pointer
to character string, which surely is NOT a valid Node.)  This doesn't
cause any backwards compatibility problems for stored rules, since
raw unanalyzed parsetrees are never stored.

Author: tglsfdc

src/backend/parser/gram.y

@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.167 2000/04/07 13:39:34 thomas Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.168 2000/05/25 22:42:17 tgl Exp $
  *
  * HISTORY
  *	  AUTHOR			DATE			MAJOR EVENT
@@ -4153,7 +4153,7 @@ row_expr: '(' row_descriptor ')' IN '(' SubSelect ')'
 				{
 					SubLink *n = makeNode(SubLink);
 					n->lefthand = $2;
-					n->oper = lcons("=", NIL);
+					n->oper = (List *) makeA_Expr(OP, "=", NULL, NULL);
 					n->useor = false;
 					n->subLinkType = ANY_SUBLINK;
 					n->subselect = $6;
@@ -4163,7 +4163,7 @@ row_expr: '(' row_descriptor ')' IN '(' SubSelect ')'
 				{
 					SubLink *n = makeNode(SubLink);
 					n->lefthand = $2;
-					n->oper = lcons("<>", NIL);
+					n->oper = (List *) makeA_Expr(OP, "<>", NULL, NULL);
 					n->useor = true;
 					n->subLinkType = ALL_SUBLINK;
 					n->subselect = $7;
@@ -4173,8 +4173,8 @@ row_expr: '(' row_descriptor ')' IN '(' SubSelect ')'
 				{
 					SubLink *n = makeNode(SubLink);
 					n->lefthand = $2;
-					n->oper = lcons($4, NIL);
-					if (strcmp($4,"<>") == 0)
+					n->oper = (List *) makeA_Expr(OP, $4, NULL, NULL);
+					if (strcmp($4, "<>") == 0)
 						n->useor = true;
 					else
 						n->useor = false;
@@ -4186,8 +4186,8 @@ row_expr: '(' row_descriptor ')' IN '(' SubSelect ')'
 				{
 					SubLink *n = makeNode(SubLink);
 					n->lefthand = $2;
-					n->oper = lcons($4, NIL);
-					if (strcmp($4,"<>") == 0)
+					n->oper = (List *) makeA_Expr(OP, $4, NULL, NULL);
+					if (strcmp($4, "<>") == 0)
 						n->useor = true;
 					else
 						n->useor = false;
@@ -4436,7 +4436,7 @@ a_expr:  c_expr
 					{
 							SubLink *n = (SubLink *)$4;
 							n->lefthand = lcons($1, NIL);
-							n->oper = lcons("=", NIL);
+							n->oper = (List *) makeA_Expr(OP, "=", NULL, NULL);
 							n->useor = false;
 							n->subLinkType = ANY_SUBLINK;
 							$$ = (Node *)n;
@@ -4463,7 +4463,7 @@ a_expr:  c_expr
 					{
 						SubLink *n = (SubLink *)$5;
 						n->lefthand = lcons($1, NIL);
-						n->oper = lcons("<>", NIL);
+						n->oper = (List *) makeA_Expr(OP, "<>", NULL, NULL);
 						n->useor = false;
 						n->subLinkType = ALL_SUBLINK;
 						$$ = (Node *)n;
@@ -4487,7 +4487,7 @@ a_expr:  c_expr
 				{
 					SubLink *n = makeNode(SubLink);
 					n->lefthand = lcons($1, NIL);
-					n->oper = lcons($2, NIL);
+					n->oper = (List *) makeA_Expr(OP, $2, NULL, NULL);
 					n->useor = false; /* doesn't matter since only one col */
 					n->subLinkType = $3;
 					n->subselect = $5;

src/backend/parser/parse_expr.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_expr.c,v 1.76 2000/04/12 17:15:26 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_expr.c,v 1.77 2000/05/25 22:42:18 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -324,23 +324,25 @@ transformExpr(ParseState *pstate, Node *expr, int precedence)
 				else
 				{
 					/* ALL, ANY, or MULTIEXPR: generate operator list */
-					char	   *op = lfirst(sublink->oper);
 					List	   *left_list = sublink->lefthand;
 					List	   *right_list = qtree->targetList;
+					char	   *op;
 					List	   *elist;
 
 					foreach(elist, left_list)
 						lfirst(elist) = transformExpr(pstate, lfirst(elist),
 													  precedence);
 
+					Assert(IsA(sublink->oper, A_Expr));
+					op = ((A_Expr *) sublink->oper)->opname;
+					sublink->oper = NIL;
+
 					/* Combining operators other than =/<> is dubious... */
 					if (length(left_list) != 1 &&
 						strcmp(op, "=") != 0 && strcmp(op, "<>") != 0)
 						elog(ERROR, "Row comparison cannot use '%s'",
 							 op);
 
-					sublink->oper = NIL;
-
 					/*
 					 * Scan subquery's targetlist to find values that will
 					 * be matched against lefthand values.	We need to

src/include/nodes/primnodes.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: primnodes.h,v 1.41 2000/04/12 17:16:40 momjian Exp $
+ * $Id: primnodes.h,v 1.42 2000/05/25 22:42:19 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -350,8 +350,8 @@ typedef struct Aggref
  * NOTE: lefthand and oper have varying meanings depending on where you look
  * in the parse/plan pipeline:
  * 1. gram.y delivers a list of the (untransformed) lefthand expressions in
- *	  lefthand, and sets oper to a one-element list containing the string
- *	  name of the operator.
+ *	  lefthand, and sets oper to a single A_Expr (not a list!) containing
+ *	  the string name of the operator, but no arguments.
  * 2. The parser's expression transformation transforms lefthand normally,
  *	  and replaces oper with a list of Oper nodes, one per lefthand
  *	  expression.  These nodes represent the parser's resolution of exactly