Error reporting improvements.

Signed-off-by: Daira Hopwood <daira@jacaranda.org>

qa/rpc-tests/test_framework/util.py

@@ -214,7 +214,7 @@ def wait_for_bitcoind_start(process, url, i):
     '''
     while True:
         if process.poll() is not None:
-            raise Exception('%s exited with status %i during initialization' % (zcashd_binary(), process.returncode))
+            raise Exception('%s node %d exited with status %i during initialization' % (zcashd_binary(), i, process.returncode))
         try:
             rpc = get_rpc_proxy(url, i)
             rpc.getblockcount()
@@ -433,7 +433,7 @@ def assert_start_raises_init_error(i, dirname, extra_args=None, expected_msg=Non
             node = start_node(i, dirname, extra_args, stderr=log_stderr)
             stop_node(node, i)
         except Exception as e:
-            assert ("%s exited" % (zcashd_binary(),)) in str(e) #node must have shutdown
+            assert ("%s node %d exited" % (zcashd_binary(), i)) in str(e) # node must have shutdown
             if expected_msg is not None:
                 log_stderr.seek(0)
                 stderr = log_stderr.read().decode('utf-8')

src/chain.h

@@ -403,6 +403,7 @@ public:
 
     uint256 GetBlockHash() const
     {
+        assert(phashBlock);
         return *phashBlock;
     }
 
@@ -432,7 +433,7 @@ public:
         return strprintf("CBlockIndex(pprev=%p, nHeight=%d, merkle=%s, hashBlock=%s)",
             pprev, nHeight,
             hashMerkleRoot.ToString(),
-            GetBlockHash().ToString());
+            phashBlock ? GetBlockHash().ToString() : "(nil)");
     }
 
     //! Check whether this block index entry is valid up to the passed validity level.

src/txdb.cpp

@@ -613,9 +613,12 @@ bool CBlockTreeDB::LoadBlockIndexGuts(
 
                 // Consistency checks
                 auto header = pindexNew->GetBlockHeader();
+                if (header.GetHash() != diskindex.GetBlockHash())
+                    return error("LoadBlockIndex(): inconsistent header vs diskindex hash: header hash = %s, diskindex hash = %s",
+                        header.GetHash().ToString(), diskindex.GetBlockHash().ToString());
                 if (header.GetHash() != pindexNew->GetBlockHash())
                     return error("LoadBlockIndex(): block header inconsistency detected: on-disk = %s, in-memory = %s",
-                       diskindex.ToString(),  pindexNew->ToString());
+                        diskindex.ToString(), pindexNew->ToString());
                 if (!CheckProofOfWork(pindexNew->GetBlockHash(), pindexNew->nBits, Params().GetConsensus()))
                     return error("LoadBlockIndex(): CheckProofOfWork failed: %s", pindexNew->ToString());