Repair problems with the result of lookup_rowtype_tupdesc() possibly being

discarded by cache flush while still in use.  This is a minimal patch that
just copies the tupdesc anywhere it could be needed across a flush.  Applied
to back branches only; Neil Conway is working on a better long-term solution
for HEAD.

src/backend/access/heap/tuptoaster.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/heap/tuptoaster.c,v 1.47 2005/01/01 05:43:06 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/heap/tuptoaster.c,v 1.47.4.1 2006/01/17 17:33:34 tgl Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -820,6 +820,7 @@ toast_flatten_tuple_attribute(Datum value,
 	if (tupleDesc == NULL)
 		return value;			/* not a composite type */
 
+	tupleDesc = CreateTupleDescCopy(tupleDesc);
 	att = tupleDesc->attrs;
 	numAttrs = tupleDesc->natts;
 
@@ -866,7 +867,10 @@ toast_flatten_tuple_attribute(Datum value,
 	 * If nothing to untoast, just return the original tuple.
 	 */
 	if (!need_change)
+	{
+		FreeTupleDesc(tupleDesc);
 		return value;
+	}
 
 	/*
 	 * Calculate the new size of the tuple.  Header size should not
@@ -903,6 +907,7 @@ toast_flatten_tuple_attribute(Datum value,
 	for (i = 0; i < numAttrs; i++)
 		if (toast_free[i])
 			pfree(DatumGetPointer(toast_values[i]));
+	FreeTupleDesc(tupleDesc);
 
 	return PointerGetDatum(new_data);
 }

src/backend/parser/parse_coerce.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/parser/parse_coerce.c,v 2.126.4.1 2006/01/12 22:29:22 neilc Exp $
+ *	  $PostgreSQL: pgsql/src/backend/parser/parse_coerce.c,v 2.126.4.2 2006/01/17 17:33:34 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -700,7 +700,7 @@ coerce_record_to_complex(ParseState *pstate, Node *node,
 						format_type_be(RECORDOID),
 						format_type_be(targetTypeId))));
 
-	tupdesc = lookup_rowtype_tupdesc(targetTypeId, -1);
+	tupdesc = CreateTupleDescCopy(lookup_rowtype_tupdesc(targetTypeId, -1));
 	newargs = NIL;
 	ucolno = 1;
 	arg = list_head(args);
@@ -758,6 +758,8 @@ coerce_record_to_complex(ParseState *pstate, Node *node,
 						format_type_be(targetTypeId)),
 				 errdetail("Input has too many columns.")));
 
+	FreeTupleDesc(tupdesc);
+
 	rowexpr = makeNode(RowExpr);
 	rowexpr->args = newargs;
 	rowexpr->row_typeid = targetTypeId;

src/backend/parser/parse_target.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/parser/parse_target.c,v 1.129.4.1 2005/12/14 16:30:20 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/parser/parse_target.c,v 1.129.4.2 2006/01/17 17:33:34 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -839,6 +839,7 @@ ExpandIndirectionStar(ParseState *pstate, A_Indirection *ind)
 
 	/* Verify it's a composite type, and get the tupdesc */
 	tupleDesc = lookup_rowtype_tupdesc(exprType(expr), exprTypmod(expr));
+	tupleDesc = CreateTupleDescCopy(tupleDesc);
 
 	/* Generate a list of references to the individual fields */
 	numAttrs = tupleDesc->natts;
@@ -889,6 +890,8 @@ ExpandIndirectionStar(ParseState *pstate, A_Indirection *ind)
 		te_list = lappend(te_list, te);
 	}
 
+	FreeTupleDesc(tupleDesc);
+
 	return te_list;
 }
 

src/backend/utils/adt/rowtypes.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/rowtypes.c,v 1.8.4.2 2005/04/30 20:04:46 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/rowtypes.c,v 1.8.4.3 2006/01/17 17:33:34 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -79,6 +79,7 @@ record_in(PG_FUNCTION_ARGS)
 		errmsg("input of anonymous composite types is not implemented")));
 	tupTypmod = -1;				/* for all non-anonymous types */
 	tupdesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
+	tupdesc = CreateTupleDescCopy(tupdesc);
 	ncolumns = tupdesc->natts;
 
 	/*
@@ -257,6 +258,7 @@ record_in(PG_FUNCTION_ARGS)
 	pfree(buf.data);
 	pfree(values);
 	pfree(nulls);
+	FreeTupleDesc(tupdesc);
 
 	PG_RETURN_HEAPTUPLEHEADER(result);
 }
@@ -284,6 +286,7 @@ record_out(PG_FUNCTION_ARGS)
 	tupType = HeapTupleHeaderGetTypeId(rec);
 	tupTypmod = HeapTupleHeaderGetTypMod(rec);
 	tupdesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
+	tupdesc = CreateTupleDescCopy(tupdesc);
 	ncolumns = tupdesc->natts;
 
 	/* Build a temporary HeapTuple control structure */
@@ -408,6 +411,7 @@ record_out(PG_FUNCTION_ARGS)
 
 	pfree(values);
 	pfree(nulls);
+	FreeTupleDesc(tupdesc);
 
 	PG_RETURN_CSTRING(buf.data);
 }
@@ -444,6 +448,7 @@ record_recv(PG_FUNCTION_ARGS)
 		errmsg("input of anonymous composite types is not implemented")));
 	tupTypmod = -1;				/* for all non-anonymous types */
 	tupdesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
+	tupdesc = CreateTupleDescCopy(tupdesc);
 	ncolumns = tupdesc->natts;
 
 	/*
@@ -593,6 +598,7 @@ record_recv(PG_FUNCTION_ARGS)
 	heap_freetuple(tuple);
 	pfree(values);
 	pfree(nulls);
+	FreeTupleDesc(tupdesc);
 
 	PG_RETURN_HEAPTUPLEHEADER(result);
 }
@@ -620,6 +626,7 @@ record_send(PG_FUNCTION_ARGS)
 	tupType = HeapTupleHeaderGetTypeId(rec);
 	tupTypmod = HeapTupleHeaderGetTypMod(rec);
 	tupdesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
+	tupdesc = CreateTupleDescCopy(tupdesc);
 	ncolumns = tupdesc->natts;
 
 	/* Build a temporary HeapTuple control structure */
@@ -722,6 +729,7 @@ record_send(PG_FUNCTION_ARGS)
 
 	pfree(values);
 	pfree(nulls);
+	FreeTupleDesc(tupdesc);
 
 	PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
 }

src/backend/utils/adt/ruleutils.c

@@ -3,7 +3,7 @@
  *				back to source text
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/ruleutils.c,v 1.188.4.2 2005/07/15 18:40:20 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/ruleutils.c,v 1.188.4.3 2006/01/17 17:33:34 tgl Exp $
  *
  *	  This software is copyrighted by Jan Wieck - Hamburg.
  *
@@ -3245,6 +3245,7 @@ get_rule_expr(Node *node, deparse_context *context,
 				if (rowexpr->row_typeid != RECORDOID)
 				{
 					tupdesc = lookup_rowtype_tupdesc(rowexpr->row_typeid, -1);
+					tupdesc = CreateTupleDescCopy(tupdesc);
 					Assert(list_length(rowexpr->args) <= tupdesc->natts);
 				}
 

src/backend/utils/cache/typcache.c

@@ -36,7 +36,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/cache/typcache.c,v 1.11 2004/12/31 22:01:25 pgsql Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/cache/typcache.c,v 1.11.4.1 2006/01/17 17:33:35 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -383,6 +383,8 @@ lookup_default_opclass(Oid type_id, Oid am_id)
  *
  * Note: returned TupleDesc points to cached copy; caller must copy it
  * if intending to scribble on it or keep a reference for a long time.
+ * ("A long time" basically means "across any possible cache flush",
+ * which typically could occur at any relation open or catalog lookup.)
  */
 TupleDesc
 lookup_rowtype_tupdesc(Oid type_id, int32 typmod)

src/pl/plperl/plperl.c

@@ -33,7 +33,7 @@
  *	  ENHANCEMENTS, OR MODIFICATIONS.
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/pl/plperl/plperl.c,v 1.67.4.4 2006/01/08 15:51:18 adunstan Exp $
+ *	  $PostgreSQL: pgsql/src/pl/plperl/plperl.c,v 1.67.4.5 2006/01/17 17:33:35 tgl Exp $
  *
  **********************************************************************/
 
@@ -705,12 +705,14 @@ plperl_call_perl_func(plperl_proc_desc *desc, FunctionCallInfo fcinfo)
 			tupType = HeapTupleHeaderGetTypeId(td);
 			tupTypmod = HeapTupleHeaderGetTypMod(td);
 			tupdesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
+			tupdesc = CreateTupleDescCopy(tupdesc);
 			/* Build a temporary HeapTuple control structure */
 			tmptup.t_len = HeapTupleHeaderGetDatumLength(td);
 			tmptup.t_data = td;
 
 			hashref = plperl_hash_from_tuple(&tmptup, tupdesc);
 			XPUSHs(sv_2mortal(hashref));
+			FreeTupleDesc(tupdesc);
 		}
 		else
 		{
@@ -1009,7 +1011,7 @@ plperl_func_handler(PG_FUNCTION_ARGS)
 		 */
 		td = get_function_tupdesc(prodesc->result_oid,
 								  (ReturnSetInfo *) fcinfo->resultinfo);
-		/* td = CreateTupleDescCopy(td); */
+		td = CreateTupleDescCopy(td);
 		attinmeta = TupleDescGetAttInMetadata(td);
 
 		tup = plperl_build_tuple_result(perlhash, attinmeta);

src/pl/plpgsql/src/pl_exec.c

@@ -3,7 +3,7 @@
  *			  procedural language
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/pl/plpgsql/src/pl_exec.c,v 1.127.4.4 2006/01/03 22:48:28 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/pl/plpgsql/src/pl_exec.c,v 1.127.4.5 2006/01/17 17:33:36 tgl Exp $
  *
  *	  This software is copyrighted by Jan Wieck - Hamburg.
  *
@@ -273,12 +273,14 @@ plpgsql_exec_function(PLpgSQL_function *func, FunctionCallInfo fcinfo)
 						tupType = HeapTupleHeaderGetTypeId(td);
 						tupTypmod = HeapTupleHeaderGetTypMod(td);
 						tupdesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
+						tupdesc = CreateTupleDescCopy(tupdesc);
 						/* Build a temporary HeapTuple control structure */
 						tmptup.t_len = HeapTupleHeaderGetDatumLength(td);
 						ItemPointerSetInvalid(&(tmptup.t_self));
 						tmptup.t_tableOid = InvalidOid;
 						tmptup.t_data = td;
 						exec_move_row(&estate, NULL, row, &tmptup, tupdesc);
+						FreeTupleDesc(tupdesc);
 					}
 					else
 					{
@@ -2948,12 +2950,14 @@ exec_assign_value(PLpgSQL_execstate *estate,
 					tupType = HeapTupleHeaderGetTypeId(td);
 					tupTypmod = HeapTupleHeaderGetTypMod(td);
 					tupdesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
+					tupdesc = CreateTupleDescCopy(tupdesc);
 					/* Build a temporary HeapTuple control structure */
 					tmptup.t_len = HeapTupleHeaderGetDatumLength(td);
 					ItemPointerSetInvalid(&(tmptup.t_self));
 					tmptup.t_tableOid = InvalidOid;
 					tmptup.t_data = td;
 					exec_move_row(estate, NULL, row, &tmptup, tupdesc);
+					FreeTupleDesc(tupdesc);
 				}
 				break;
 			}
@@ -2990,12 +2994,14 @@ exec_assign_value(PLpgSQL_execstate *estate,
 					tupType = HeapTupleHeaderGetTypeId(td);
 					tupTypmod = HeapTupleHeaderGetTypMod(td);
 					tupdesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
+					tupdesc = CreateTupleDescCopy(tupdesc);
 					/* Build a temporary HeapTuple control structure */
 					tmptup.t_len = HeapTupleHeaderGetDatumLength(td);
 					ItemPointerSetInvalid(&(tmptup.t_self));
 					tmptup.t_tableOid = InvalidOid;
 					tmptup.t_data = td;
 					exec_move_row(estate, rec, NULL, &tmptup, tupdesc);
+					FreeTupleDesc(tupdesc);
 				}
 				break;
 			}

src/pl/plpython/plpython.c

@@ -29,7 +29,7 @@
  * MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  *
  * IDENTIFICATION
- *	$PostgreSQL: pgsql/src/pl/plpython/plpython.c,v 1.58.4.4 2006/01/10 00:33:48 neilc Exp $
+ *	$PostgreSQL: pgsql/src/pl/plpython/plpython.c,v 1.58.4.5 2006/01/17 17:33:37 tgl Exp $
  *
  *********************************************************************
  */
@@ -861,6 +861,7 @@ PLy_function_build_args(FunctionCallInfo fcinfo, PLyProcedure * proc)
 					tupType = HeapTupleHeaderGetTypeId(td);
 					tupTypmod = HeapTupleHeaderGetTypMod(td);
 					tupdesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
+					tupdesc = CreateTupleDescCopy(tupdesc);
 
 					/* Set up I/O funcs if not done yet */
 					if (proc->args[i].is_rowtype != 1)
@@ -871,6 +872,7 @@ PLy_function_build_args(FunctionCallInfo fcinfo, PLyProcedure * proc)
 					tmptup.t_data = td;
 
 					arg = PLyDict_FromTuple(&(proc->args[i]), &tmptup, tupdesc);
+					FreeTupleDesc(tupdesc);
 				}
 			}
 			else

src/pl/tcl/pltcl.c

@@ -31,7 +31,7 @@
  *	  ENHANCEMENTS, OR MODIFICATIONS.
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/pl/tcl/pltcl.c,v 1.94 2004/11/21 21:17:05 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/pl/tcl/pltcl.c,v 1.94.4.1 2006/01/17 17:33:37 tgl Exp $
  *
  **********************************************************************/
 
@@ -533,6 +533,7 @@ pltcl_func_handler(PG_FUNCTION_ARGS)
 					tupType = HeapTupleHeaderGetTypeId(td);
 					tupTypmod = HeapTupleHeaderGetTypMod(td);
 					tupdesc = lookup_rowtype_tupdesc(tupType, tupTypmod);
+					tupdesc = CreateTupleDescCopy(tupdesc);
 					/* Build a temporary HeapTuple control structure */
 					tmptup.t_len = HeapTupleHeaderGetDatumLength(td);
 					tmptup.t_data = td;
@@ -541,6 +542,7 @@ pltcl_func_handler(PG_FUNCTION_ARGS)
 					pltcl_build_tuple_argument(&tmptup, tupdesc, &list_tmp);
 					Tcl_DStringAppendElement(&tcl_cmd,
 											 Tcl_DStringValue(&list_tmp));
+					FreeTupleDesc(tupdesc);
 				}
 			}
 			else