From 620dcb5b9dd3dc2c9286aa50d4e03487ca341308 Mon Sep 17 00:00:00 2001
From: Chip Morningstar <chip@fudco.com>
Date: Fri, 7 May 2021 17:47:11 -0700
Subject: [PATCH] fix: bug #3022, off-by-one in slog deliveryNum

---
 packages/SwingSet/src/kernel/slogger.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/SwingSet/src/kernel/slogger.js b/packages/SwingSet/src/kernel/slogger.js
index afab4eb80ee..2efb8d0d89e 100644
--- a/packages/SwingSet/src/kernel/slogger.js
+++ b/packages/SwingSet/src/kernel/slogger.js
@@ -143,13 +143,13 @@ export function makeSlogger(slogCallbacks, writeObj) {
       crankNum = newCrankNum;
       const when = { crankNum, vatID, deliveryNum };
       write({ type: 'deliver', ...when, kd, vd });
-      deliveryNum += 1;
       syscallNum = 0;
 
       // dr: deliveryResult
       function finish(dr) {
         assertOldState(DELIVERY, 'delivery-finish called twice?');
         write({ type: 'deliver-result', ...when, dr });
+        deliveryNum += 1;
         state = IDLE;
       }
       return harden(finish);