Make fReindex atomic to avoid race

src/validation.cpp

@@ -66,7 +66,7 @@ CWaitableCriticalSection csBestBlock;
 CConditionVariable cvBlockChange;
 int nScriptCheckThreads = 0;
 std::atomic_bool fImporting(false);
-bool fReindex = false;
+std::atomic_bool fReindex(false);
 bool fTxIndex = false;
 bool fHavePruned = false;
 bool fPruneMode = false;
@@ -3523,7 +3523,7 @@ bool static LoadBlockIndexDB(const CChainParams& chainparams)
     // Check whether we need to continue reindexing
     bool fReindexing = false;
     pblocktree->ReadReindexing(fReindexing);
-    fReindex |= fReindexing;
+    if(fReindexing) fReindex = true;
 
     // Check whether we have a transaction index
     pblocktree->ReadFlag("txindex", fTxIndex);

src/validation.h

@@ -167,7 +167,7 @@ extern const std::string strMessageMagic;
 extern CWaitableCriticalSection csBestBlock;
 extern CConditionVariable cvBlockChange;
 extern std::atomic_bool fImporting;
-extern bool fReindex;
+extern std::atomic_bool fReindex;
 extern int nScriptCheckThreads;
 extern bool fTxIndex;
 extern bool fIsBareMultisigStd;