https://github.com/bitcoin/bitcoin/blob/68f3c7eb080e461cfeac37f8db7034fe507241d0/src/prevector.h#L152-L158

I'm opening an issue as its fix is too tiny to become a pull request.

Can be solved by renaming the struct to
```c
     struct indirect_contents { 
         size_type capacity; 
         char* indirect; 
     }; 
```
{
    if (!fCheckBlockIndex) {
        return;
    }
    LOCK(cs_main);
    
    
    
    if (m_chain.Height() < 0) {
        assert(m_blockman.m_block_index.size() <= 1);
        return;
    }
    
    std::multimap<CBlockIndex*,CBlockIndex*> forward;
    for (const std::pair<const uint256, CBlockIndex*>& entry : m_blockman.m_block_index) {
        forward.insert(std::make_pair(entry.second->pprev, entry.second));
    }
    assert(forward.size() == m_blockman.m_block_index.size());
    std::pair<std::multimap<CBlockIndex*,CBlockIndex*>::iterator,std::multimap<CBlockIndex*,CBlockIndex*>::iterator> rangeGenesis = forward.equal_range(nullptr);
    CBlockIndex *pindex = rangeGenesis.first->second;
    rangeGenesis.first++;
    assert(rangeGenesis.first == rangeGenesis.second);