From ae70e8a344818482421828902802e2454d16ad5c Mon Sep 17 00:00:00 2001
From: UdjinM6 <UdjinM6@users.noreply.github.com>
Date: Fri, 1 Feb 2019 12:07:03 +0300
Subject: [PATCH] Fix negative "keys left since backup" (#2671)

---
 src/wallet/wallet.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 8f480e7812..798dd74756 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -4262,8 +4262,10 @@ void CWallet::KeepKey(int64_t nIndex)
     if (fFileBacked)
     {
         CWalletDB walletdb(strWalletFile);
-        walletdb.ErasePool(nIndex);
-        nKeysLeftSinceAutoBackup = nWalletBackups ? nKeysLeftSinceAutoBackup - 1 : 0;
+        if (walletdb.ErasePool(nIndex))
+            --nKeysLeftSinceAutoBackup;
+        if (!nWalletBackups)
+            nKeysLeftSinceAutoBackup = 0;
     }
     LogPrintf("keypool keep %d\n", nIndex);
 }