From dd0df81ebdbf705f7ad386c7229bf1bbc3125f62 Mon Sep 17 00:00:00 2001
From: Matt Corallo <git@bluematt.me>
Date: Tue, 29 Nov 2016 21:25:39 -0800
Subject: [PATCH] Document ConnectBlock connectTrace postconditions

---
 src/validation.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/validation.cpp b/src/validation.cpp
index 0983c1f76..3bcbf33d6 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -2164,6 +2164,10 @@ struct ConnectTrace {
 /**
  * Connect a new block to chainActive. pblock is either NULL or a pointer to a CBlock
  * corresponding to pindexNew, to bypass loading it again from disk.
+ *
+ * The block is always added to connectTrace (either after loading from disk or by copying
+ * pblock) - if that is not intended, care must be taken to remove the last entry in
+ * blocksConnected in case of failure.
  */
 bool static ConnectTip(CValidationState& state, const CChainParams& chainparams, CBlockIndex* pindexNew, const std::shared_ptr<const CBlock>& pblock, ConnectTrace& connectTrace)
 {