Fix access to just-closed relcache entry.

It might be impossible for this to cause a problem in non-debug builds,
since there'd be no opportunity for the relcache entry to get recycled
before the fetch.  It blows up nicely with -DRELCACHE_FORCE_RELEASE plus
valgrind, though.

Evidently introduced by careless refactoring in commit f0e44751d.
Back-patch accordingly.

Discussion: https://postgr.es/m/27543.1528758304@sss.pgh.pa.us

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 0e95037dcf4d95e1f95f2e8b8ba1233ab5425d8e..d20991a1e56f70d561e486eab28e01c4892e69bf 100644 (file)
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -11922,12 +11922,12 @@ ATExecDropInherit(Relation rel, RangeVar *parent, LOCKMODE lockmode)
        /* Off to RemoveInheritance() where most of the work happens */
        RemoveInheritance(rel, parent_rel);
 
-       /* keep our lock on the parent relation until commit */
-       heap_close(parent_rel, NoLock);
-
        ObjectAddressSet(address, RelationRelationId,
                                         RelationGetRelid(parent_rel));
 
+       /* keep our lock on the parent relation until commit */
+       heap_close(parent_rel, NoLock);
+
        return address;
 }