Fix breakage in AlterFunction().

An ALTER FUNCTION command that tried to update both the function's
proparallel property and its proconfig list failed to do the former,
because it stored the new proparallel value into a tuple that was
no longer the interesting one.  Carelessness in 7aea8e4f2.

(I did not bother with a regression test, because the only likely
future breakage would be for someone to ignore the comment I added
and add some other field update after the heap_modify_tuple step.
A test using existing function properties could not catch that.)

Per report from Bryn Llewellyn.  Back-patch to all supported branches.

Discussion: https://postgr.es/m/8AC9A37F-99BD-446F-A2F7-B89AD0022774@yugabyte.com

diff --git a/src/backend/commands/functioncmds.c b/src/backend/commands/functioncmds.c
index 7de844b2cadff52a6d295eb66c30c0278f58d8e1..a2275a0c6bd469efdd4bd649d0136dc68caaad38 100644 (file)
--- a/src/backend/commands/functioncmds.c
+++ b/src/backend/commands/functioncmds.c
@@ -1253,6 +1253,8 @@ AlterFunction(ParseState *pstate, AlterFunctionStmt *stmt)
                    (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                     errmsg("ROWS is not applicable when function does not return a set")));
    }
+   if (parallel_item)
+       procForm->proparallel = interpret_func_parallel(parallel_item);
    if (set_items)
    {
        Datum       datum;
@@ -1287,8 +1289,7 @@ AlterFunction(ParseState *pstate, AlterFunctionStmt *stmt)
        tup = heap_modify_tuple(tup, RelationGetDescr(rel),
                                repl_val, repl_null, repl_repl);
    }
-   if (parallel_item)
-       procForm->proparallel = interpret_func_parallel(parallel_item);
+   /* DO NOT put more touches of procForm below here; it's now dangling. */
 
    /* Do the update */
    CatalogTupleUpdate(rel, &tup->t_self, tup);