From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Thu, 8 Nov 2012 16:34:37 +0000 (-0500)
Subject: Don't trash input list structure in does_not_exist_skipping().
X-Git-Tag: REL9_2_2~43
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=03787f63921e37c123ceff712ed405c5172e765d;p=postgresql

Don't trash input list structure in does_not_exist_skipping().

The trigger and rule cases need to split up the input name list, but
they mustn't corrupt the passed-in data structure, since it could be part
of a cached utility-statement parsetree.  Per bug #7641.
---

diff --git a/src/backend/commands/dropcmds.c b/src/backend/commands/dropcmds.c
index 1b8529ed84..36b09ca4b8 100644
--- a/src/backend/commands/dropcmds.c
+++ b/src/backend/commands/dropcmds.c
@@ -203,13 +203,13 @@ does_not_exist_skipping(ObjectType objtype, List *objname, List *objargs)
 		case OBJECT_TRIGGER:
 			msg = gettext_noop("trigger \"%s\" for table \"%s\" does not exist, skipping");
 			name = strVal(llast(objname));
-			args = NameListToString(list_truncate(objname,
+			args = NameListToString(list_truncate(list_copy(objname),
 												  list_length(objname) - 1));
 			break;
 		case OBJECT_RULE:
 			msg = gettext_noop("rule \"%s\" for relation \"%s\" does not exist, skipping");
 			name = strVal(llast(objname));
-			args = NameListToString(list_truncate(objname,
+			args = NameListToString(list_truncate(list_copy(objname),
 												  list_length(objname) - 1));
 			break;
 		case OBJECT_FDW: