Pass ZCIncrementalMerkleTree to wallet to prevent race conditions

src/main.cpp

@@ -2398,13 +2398,16 @@ bool static DisconnectTip(CValidationState &state) {
     mempool.check(pcoinsTip);
     // Update chainActive and related variables.
     UpdateTip(pindexDelete->pprev);
+    // Get the current commitment tree
+    ZCIncrementalMerkleTree newTree;
+    assert(pcoinsTip->GetAnchorAt(pcoinsTip->GetBestAnchor(), newTree));
     // Let wallets know transactions went from 1-confirmed to
     // 0-confirmed or conflicted:
     BOOST_FOREACH(const CTransaction &tx, block.vtx) {
         SyncWithWallets(tx, NULL);
     }
     // Update cached incremental witnesses
-    GetMainSignals().ChainTip(pindexDelete, &block, false);
+    GetMainSignals().ChainTip(pindexDelete, &block, newTree, false);
     return true;
 }
 
@@ -2429,6 +2432,9 @@ bool static ConnectTip(CValidationState &state, CBlockIndex *pindexNew, CBlock *
             return AbortNode(state, "Failed to read block");
         pblock = █
     }
+    // Get the current commitment tree
+    ZCIncrementalMerkleTree oldTree;
+    assert(pcoinsTip->GetAnchorAt(pcoinsTip->GetBestAnchor(), oldTree));
     // Apply the block atomically to the chain state.
     int64_t nTime2 = GetTimeMicros(); nTimeReadFromDisk += nTime2 - nTime1;
     int64_t nTime3;
@@ -2471,7 +2477,7 @@ bool static ConnectTip(CValidationState &state, CBlockIndex *pindexNew, CBlock *
         SyncWithWallets(tx, pblock);
     }
     // Update cached incremental witnesses
-    GetMainSignals().ChainTip(pindexNew, pblock, true);
+    GetMainSignals().ChainTip(pindexNew, pblock, oldTree, true);
 
     int64_t nTime6 = GetTimeMicros(); nTimePostConnect += nTime6 - nTime5; nTimeTotal += nTime6 - nTime1;
     LogPrint("bench", "  - Connect postprocess: %.2fms [%.2fs]\n", (nTime6 - nTime5) * 0.001, nTimePostConnect * 0.000001);