message: test: * -> &
  This changes background_cs from being a pointer to a reference to work
  around a gcc false warning. Also, this makes the test easier to read.
  Fixes
  Can be reviewed with --ignore-all-space.
diff: @@ -107,20 +107,21 @@ BOOST_FIXTURE_TEST_CASE(chainstate_update_tip, TestChain100Setup)
  curr_tip = ::g_best_block;
  - CChainState* background_cs;
  -
  BOOST_CHECK_EQUAL(chainman.GetAll().size(), 2);
  +
  + CChainState& background_cs{*[&] {
  for (CChainState* cs : chainman.GetAll()) {
  if (cs != &chainman.ActiveChainstate()) {
  - background_cs = cs;
  + return cs;
  }
  }
  - BOOST_CHECK(background_cs);
  + assert(false);
  + }()};
  // Create a block to append to the validation chain.
  std::vector<CMutableTransaction> noTxns;
  CScript scriptPubKey = CScript() << ToByteVector(coinbaseKey.GetPubKey()) << OP_CHECKSIG;
  - CBlock validation_block = this->CreateBlock(noTxns, scriptPubKey, *background_cs);
  + CBlock validation_block = this->CreateBlock(noTxns, scriptPubKey, background_cs);
  auto pblock = std::make_shared<const CBlock>(validation_block);
  BlockValidationState state;
  CBlockIndex* pindex = nullptr;
  @@ -133,15 +134,15 @@ BOOST_FIXTURE_TEST_CASE(chainstate_update_tip, TestChain100Setup)
  LOCK(::cs_main);
  bool checked = CheckBlock(*pblock, state, chainparams.GetConsensus());
  BOOST_CHECK(checked);
  - bool accepted = background_cs->AcceptBlock(
  + bool accepted = background_cs.AcceptBlock(
  pblock, state, &pindex, true, nullptr, &newblock);
  BOOST_CHECK(accepted);
  }
  // UpdateTip is called here
  - bool block_added = background_cs->ActivateBestChain(state, pblock);
  + bool block_added = background_cs.ActivateBestChain(state, pblock);
  // Ensure tip is as expected
  - BOOST_CHECK_EQUAL(background_cs->m_chain.Tip()->GetBlockHash(), validation_block.GetHash());
  + BOOST_CHECK_EQUAL(background_cs.m_chain.Tip()->GetBlockHash(), validation_block.GetHash());
  // g_best_block should be unchanged after adding a block to the background
  // validation chain.
  