From 063560bb8e1e3658df858266d593a0ee2d053423 Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Sat, 6 Jan 2007 19:14:17 +0000
Subject: [PATCH] Fix filtered_base_yylex() to save and restore base_yylval and
base_yylloc properly when doing a lookahead. The lack of this was causing
various interesting misbehaviors when one tries to use "with" as a plain
identifier.
---
src/backend/parser/parser.c | 26 +++++++++++++++++++++-----
1 file changed, 21 insertions(+), 5 deletions(-)
diff --git a/src/backend/parser/parser.c b/src/backend/parser/parser.c
index 8490f8ab8b8..c007613cc4e 100644
--- a/src/backend/parser/parser.c
+++ b/src/backend/parser/parser.c
@@ -14,7 +14,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/parser/parser.c,v 1.69 2007/01/05 22:19:34 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/parser/parser.c,v 1.70 2007/01/06 19:14:17 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -28,8 +28,10 @@
List *parsetree; /* result of parsing is left here */
-static int lookahead_token; /* one-token lookahead */
-static bool have_lookahead; /* lookahead_token set? */
+static bool have_lookahead; /* is lookahead info valid? */
+static int lookahead_token; /* one-token lookahead */
+static YYSTYPE lookahead_yylval; /* yylval for lookahead token */
+static YYLTYPE lookahead_yylloc; /* yylloc for lookahead token */
/*
@@ -77,11 +79,16 @@ int
filtered_base_yylex(void)
{
int cur_token;
+ int next_token;
+ YYSTYPE cur_yylval;
+ YYLTYPE cur_yylloc;
/* Get next token --- we might already have it */
if (have_lookahead)
{
cur_token = lookahead_token;
+ base_yylval = lookahead_yylval;
+ base_yylloc = lookahead_yylloc;
have_lookahead = false;
}
else
@@ -102,8 +109,10 @@ filtered_base_yylex(void)
* (perhaps for SQL99 recursive queries), come back and simplify
* this code.
*/
- lookahead_token = base_yylex();
- switch (lookahead_token)
+ cur_yylval = base_yylval;
+ cur_yylloc = base_yylloc;
+ next_token = base_yylex();
+ switch (next_token)
{
case CASCADED:
cur_token = WITH_CASCADED;
@@ -115,7 +124,14 @@ filtered_base_yylex(void)
cur_token = WITH_CHECK;
break;
default:
+ /* save the lookahead token for next time */
+ lookahead_token = next_token;
+ lookahead_yylval = base_yylval;
+ lookahead_yylloc = base_yylloc;
have_lookahead = true;
+ /* and back up the output info to cur_token */
+ base_yylval = cur_yylval;
+ base_yylloc = cur_yylloc;
break;
}
break;
--
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