diff --git a/src/chain.cpp b/src/chain.cpp
index b8158f7b0b..0f898bafd5 100644
--- a/src/chain.cpp
+++ b/src/chain.cpp
@@ -4,6 +4,7 @@
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <chain.h>
+#include <tinyformat.h>
 #include <util/time.h>
 
 std::string CBlockFileInfo::ToString() const
@@ -11,6 +12,12 @@ std::string CBlockFileInfo::ToString() const
     return strprintf("CBlockFileInfo(blocks=%u, size=%u, heights=%u...%u, time=%s...%s)", nBlocks, nSize, nHeightFirst, nHeightLast, FormatISO8601Date(nTimeFirst), FormatISO8601Date(nTimeLast));
 }
 
+std::string CBlockIndex::ToString() const
+{
+    return strprintf("CBlockIndex(pprev=%p, nHeight=%d, merkle=%s, hashBlock=%s)",
+                     pprev, nHeight, hashMerkleRoot.ToString(), GetBlockHash().ToString());
+}
+
 void CChain::SetTip(CBlockIndex *pindex) {
     if (pindex == nullptr) {
         vChain.clear();
diff --git a/src/chain.h b/src/chain.h
index ecc2ae732f..627a3dfab2 100644
--- a/src/chain.h
+++ b/src/chain.h
@@ -11,7 +11,6 @@
 #include <flatfile.h>
 #include <primitives/block.h>
 #include <sync.h>
-#include <tinyformat.h>
 #include <uint256.h>
 
 #include <vector>
@@ -263,6 +262,7 @@ public:
 
     uint256 GetBlockHash() const
     {
+        assert(phashBlock != nullptr);
         return *phashBlock;
     }
 
@@ -301,13 +301,7 @@ public:
         return pbegin[(pend - pbegin) / 2];
     }
 
-    std::string ToString() const
-    {
-        return strprintf("CBlockIndex(pprev=%p, nHeight=%d, merkle=%s, hashBlock=%s)",
-            pprev, nHeight,
-            hashMerkleRoot.ToString(),
-            GetBlockHash().ToString());
-    }
+    std::string ToString() const;
 
     //! Check whether this block index entry is valid up to the passed validity level.
     bool IsValid(enum BlockStatus nUpTo = BLOCK_VALID_TRANSACTIONS) const
@@ -402,7 +396,7 @@ public:
         READWRITE(obj.nNonce);
     }
 
-    uint256 GetBlockHash() const
+    uint256 ConstructBlockHash() const
     {
         CBlockHeader block;
         block.nVersion = nVersion;
@@ -414,16 +408,8 @@ public:
         return block.GetHash();
     }
 
-
-    std::string ToString() const
-    {
-        std::string str = "CDiskBlockIndex(";
-        str += CBlockIndex::ToString();
-        str += strprintf("\n                hashBlock=%s, hashPrev=%s)",
-            GetBlockHash().ToString(),
-            hashPrev.ToString());
-        return str;
-    }
+    uint256 GetBlockHash() = delete;
+    std::string ToString() = delete;
 };
 
 /** An in-memory indexed chain of blocks. */
diff --git a/src/test/fuzz/chain.cpp b/src/test/fuzz/chain.cpp
index 8c0ed32d51..01edb06138 100644
--- a/src/test/fuzz/chain.cpp
+++ b/src/test/fuzz/chain.cpp
@@ -23,7 +23,7 @@ FUZZ_TARGET(chain)
     disk_block_index->phashBlock = &zero;
     {
         LOCK(::cs_main);
-        (void)disk_block_index->GetBlockHash();
+        (void)disk_block_index->ConstructBlockHash();
         (void)disk_block_index->GetBlockPos();
         (void)disk_block_index->GetBlockTime();
         (void)disk_block_index->GetBlockTimeMax();
@@ -31,7 +31,6 @@ FUZZ_TARGET(chain)
         (void)disk_block_index->GetUndoPos();
         (void)disk_block_index->HaveTxsDownloaded();
         (void)disk_block_index->IsValid();
-        (void)disk_block_index->ToString();
     }
 
     const CBlockHeader block_header = disk_block_index->GetBlockHeader();
diff --git a/src/txdb.cpp b/src/txdb.cpp
index c048c2d92a..bad3bb80a9 100644
--- a/src/txdb.cpp
+++ b/src/txdb.cpp
@@ -310,7 +310,7 @@ bool CBlockTreeDB::LoadBlockIndexGuts(const Consensus::Params& consensusParams,
             CDiskBlockIndex diskindex;
             if (pcursor->GetValue(diskindex)) {
                 // Construct block index object
-                CBlockIndex* pindexNew = insertBlockIndex(diskindex.GetBlockHash());
+                CBlockIndex* pindexNew = insertBlockIndex(diskindex.ConstructBlockHash());
                 pindexNew->pprev          = insertBlockIndex(diskindex.hashPrev);
                 pindexNew->nHeight        = diskindex.nHeight;
                 pindexNew->nFile          = diskindex.nFile;
diff --git a/src/validation.cpp b/src/validation.cpp
index 9b39350fed..d64ef4df0b 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -2266,7 +2266,6 @@ bool CChainState::ConnectBlock(const CBlock& block, BlockValidationState& state,
         m_blockman.m_dirty_blockindex.insert(pindex);
     }
 
-    assert(pindex->phashBlock);
     // add this block to the view's block chain
     view.SetBestBlock(pindex->GetBlockHash());