Index: src/backend/parser/parse_clause.c
===================================================================
RCS file: /opt/src/cvs/pgsql/src/backend/parser/parse_clause.c,v
retrieving revision 1.92
diff -c -r1.92 parse_clause.c
*** src/backend/parser/parse_clause.c	12 May 2002 23:43:03 -0000	1.92
--- src/backend/parser/parse_clause.c	15 May 2002 22:55:37 -0000
***************
*** 61,67 ****
  static List *addTargetToSortList(TargetEntry *tle, List *sortlist,
  					List *targetlist, List *opname);
  static bool exprIsInSortList(Node *expr, List *sortList, List *targetList);
! 
  
  /*
   * transformFromClause -
--- 61,70 ----
  static List *addTargetToSortList(TargetEntry *tle, List *sortlist,
  					List *targetlist, List *opname);
  static bool exprIsInSortList(Node *expr, List *sortList, List *targetList);
! static void checkParameterVisibility(ParseState *pstate,
! 								RangeTblRef *rtr,
! 								RangeFunction *rangefunc,
! 								List *containedRels);
  
  /*
   * transformFromClause -
***************
*** 545,550 ****
--- 548,559 ----
  
  		rtr = transformRangeFunction(pstate, (RangeFunction *) n);
  		*containedRels = makeListi1(rtr->rtindex);
+ 
+ 		/*
+ 		 * Make sure we've only been given valid parameters, i.e.
+ 		 * we should not see vars from sibling FROM nodes.
+ 		 */
+ 		checkParameterVisibility(pstate, rtr, (RangeFunction *) n, *containedRels);
  		return (Node *) rtr;
  	}
  	else if (IsA(n, JoinExpr))
***************
*** 1377,1380 ****
--- 1386,1445 ----
  			return true;
  	}
  	return false;
+ }
+ 
+ /* checkParameterVisibility()
+  *	  Make sure we don't try to access vars from
+  *	  sibling FROM nodes as RangeFunction parameters.
+  */
+ static void
+ checkParameterVisibility(ParseState *pstate, RangeTblRef *rtr, RangeFunction *rangefunc, List *containedRels)
+ {
+ 	FuncCall	   *funccallnode = (FuncCall *) rangefunc->funccallnode;
+ 	List		   *args = funccallnode->args;
+ 	List		   *save_namespace;
+ 	List		   *clause_varnos,
+ 				   *l;
+ 
+ 	/*
+ 	 * This is a tad tricky, for two reasons.  First, the namespace that
+ 	 * the join expression should see is just the any outer references
+ 	 * from upper pstate levels. So, temporarily set this pstate's namespace
+ 	 * accordingly.  (We need not check for refname conflicts, because
+ 	 * transformFromClauseItem() already did.) NOTE: this code is OK only
+ 	 * because a RangeFunction can't legally alter the namespace by causing
+ 	 * implicit relation refs to be added.
+ 	 */
+ 	save_namespace = pstate->p_namespace;
+ 	pstate->p_namespace = makeList1(rtr);
+ 
+ 	/* transform the list of arguments */
+ 	foreach(args, funccallnode->args)
+ 	{
+ 		lfirst(args) = transformExpr(pstate, (Node *) lfirst(args));
+ 
+ 		/*
+ 		 * Second, we need to check that the ON condition doesn't refer to any
+ 		 * rels outside the input subtrees of the JOIN.  It could do that
+ 		 * despite our hack on the namespace if it uses fully-qualified names.
+ 		 * So, grovel through the transformed clause and make sure there are
+ 		 * no bogus references.  (Outer references are OK, and are ignored
+ 		 * here.)
+ 		 */
+ 
+ 		clause_varnos = pull_varnos(lfirst(args));
+ 		foreach(l, clause_varnos)
+ 		{
+ 			int			varno = lfirsti(l);
+ 
+ 			if (!intMember(varno, containedRels))
+ 			{
+ 				elog(ERROR, "Function relation in FROM clause may not refer to other relation, \"%s\"",
+ 					 rt_fetch(varno, pstate->p_rtable)->eref->aliasname);
+ 			}
+ 		}
+ 		freeList(clause_varnos);
+ 
+ 	}
+ 	pstate->p_namespace = save_namespace;
  }