Use C99 designated designators in a couple of places

This makes the arrays somewhat easier to read.

Author: Álvaro Herrera <alvherre@kurilemu.de>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Jelte Fennema-Nio <postgres@jeltef.nl>
Discussion: https://postgr.es/m/202601281204.sdxbr5qvpunk@alvherre.pgsql

src/backend/access/heap/heapam.c

@@ -111,11 +111,11 @@ static HeapTuple ExtractReplicaIdentity(Relation relation, HeapTuple tp, bool ke
 
 
 /*
- * Each tuple lock mode has a corresponding heavyweight lock, and one or two
- * corresponding MultiXactStatuses (one to merely lock tuples, another one to
- * update them).  This table (and the macros below) helps us determine the
- * heavyweight lock mode and MultiXactStatus values to use for any particular
- * tuple lock strength.
+ * This table lists the heavyweight lock mode that corresponds to each tuple
+ * lock mode, as well as one or two corresponding MultiXactStatus values:
+ * .lockstatus to merely lock tuples, and .updstatus to update them.  The
+ * latter is set to -1 if the corresponding tuple lock mode does not allow
+ * updating tuples -- see get_mxact_status_for_lock().
  *
  * These interact with InplaceUpdateTupleLock, an alias for ExclusiveLock.
  *
@@ -127,29 +127,30 @@ static const struct
 	LOCKMODE	hwlock;
 	int			lockstatus;
 	int			updstatus;
-}
+}			tupleLockExtraInfo[] =
 
-			tupleLockExtraInfo[MaxLockTupleMode + 1] =
 {
-	{							/* LockTupleKeyShare */
-		AccessShareLock,
-		MultiXactStatusForKeyShare,
-		-1						/* KeyShare does not allow updating tuples */
+	[LockTupleKeyShare] = {
+		.hwlock = AccessShareLock,
+		.lockstatus = MultiXactStatusForKeyShare,
+		/* KeyShare does not allow updating tuples */
+		.updstatus = -1
 	},
-	{							/* LockTupleShare */
-		RowShareLock,
-		MultiXactStatusForShare,
-		-1						/* Share does not allow updating tuples */
+	[LockTupleShare] = {
+		.hwlock = RowShareLock,
+		.lockstatus = MultiXactStatusForShare,
+		/* Share does not allow updating tuples */
+		.updstatus = -1
 	},
-	{							/* LockTupleNoKeyExclusive */
-		ExclusiveLock,
-		MultiXactStatusForNoKeyUpdate,
-		MultiXactStatusNoKeyUpdate
+	[LockTupleNoKeyExclusive] = {
+		.hwlock = ExclusiveLock,
+		.lockstatus = MultiXactStatusForNoKeyUpdate,
+		.updstatus = MultiXactStatusNoKeyUpdate
 	},
-	{							/* LockTupleExclusive */
-		AccessExclusiveLock,
-		MultiXactStatusForUpdate,
-		MultiXactStatusUpdate
+	[LockTupleExclusive] = {
+		.hwlock = AccessExclusiveLock,
+		.lockstatus = MultiXactStatusForUpdate,
+		.updstatus = MultiXactStatusUpdate
 	}
 };
 

src/backend/postmaster/bgworker.c

@@ -120,22 +120,28 @@ static const struct
 
 {
 	{
-		"ParallelWorkerMain", ParallelWorkerMain
+		.fn_name = "ParallelWorkerMain",
+		.fn_addr = ParallelWorkerMain
 	},
 	{
-		"ApplyLauncherMain", ApplyLauncherMain
+		.fn_name = "ApplyLauncherMain",
+		.fn_addr = ApplyLauncherMain
 	},
 	{
-		"ApplyWorkerMain", ApplyWorkerMain
+		.fn_name = "ApplyWorkerMain",
+		.fn_addr = ApplyWorkerMain
 	},
 	{
-		"ParallelApplyWorkerMain", ParallelApplyWorkerMain
+		.fn_name = "ParallelApplyWorkerMain",
+		.fn_addr = ParallelApplyWorkerMain
 	},
 	{
-		"TableSyncWorkerMain", TableSyncWorkerMain
+		.fn_name = "TableSyncWorkerMain",
+		.fn_addr = TableSyncWorkerMain
 	},
 	{
-		"SequenceSyncWorkerMain", SequenceSyncWorkerMain
+		.fn_name = "SequenceSyncWorkerMain",
+		.fn_addr = SequenceSyncWorkerMain
 	}
 };