Fix domain_in() bug exhibited by Darcy Buskermolen. The idea of an EState

that's shorter-lived than the expression state being evaluated in it really
doesn't work :-( --- we end up with fn_extra caches getting deleted while
still in use.  Rather than abandon the notion of caching expression state
across domain_in calls altogether, I chose to make domain_in a bit cozier
with ExprContext.  All we really need for evaluating variable-free
expressions is an ExprContext, not an EState, so I invented the notion of a
"standalone" ExprContext.  domain_in can prevent resource leakages by doing
a ReScanExprContext on this rather than having to free it entirely; so we
can make the ExprContext have the same lifespan (and particularly the same
per_query memory context) as the expression state structs.

1 files changed, 2 insertions, 1 deletions

diff --git a/src/include/executor/executor.h b/src/include/executor/executor.h
index d926d8b5c5c..b2baec841bc 100644
--- a/src/include/executor/executor.h
+++ b/src/include/executor/executor.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/executor/executor.h,v 1.127 2006/06/16 18:42:23 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/executor/executor.h,v 1.128 2006/08/04 21:33:36 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -224,6 +224,7 @@ extern void end_tup_output(TupOutputState *tstate);
 extern EState *CreateExecutorState(void);
 extern void FreeExecutorState(EState *estate);
 extern ExprContext *CreateExprContext(EState *estate);
+extern ExprContext *CreateStandaloneExprContext(void);
 extern void FreeExprContext(ExprContext *econtext);
 extern void ReScanExprContext(ExprContext *econtext);