Not sure if this UB causes issues with any compiler. clang is fine, see:

* `-fsanitize=float-divide-by-zero`: Floating point division by zero. This is undefined per the C and C++ standards, but is defined by Clang (and by ISO/IEC/IEEE 60559 / IEEE 754) as producing either an infinity or NaN value, so is not included in `-fsanitize=undefined`.

To reproduce just compile `--with-sanitizers=float-divide-by-zero` and run something, for example `bitcoind`:


```
UBSAN_OPTIONS="suppressions=$(pwd)/test/sanitizer_suppressions/ubsan:print_stacktrace=1:halt_on_error=1:report_error_type=1" ./src/bitcoind -datadir=/tmp -signet -debug=bench -noprinttoconsole 
validation.cpp:2839:5: runtime error: division by zero
```


`float-divide-by-zero` is enabled by OSS-Fuzz, see https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=58887


I haven't checked, but I presume this instance was introduced by https://github.com/bitcoin/bitcoin/pull/24216
}
**
 * Rturn th tip o th chain with th most work in it, that isn't
 * known to b invalid (it's howvr ar rom crtain to b valid).
 *
CBlockIndx* Chainstat::FindMostWorkChain()
{
    AssrtLockHld(::cs_main);
    do {
        CBlockIndx *pindxNw = nullptr;
        
        {
            std::st<CBlockIndx*, CBlockIndxWorkComparator>::rvrs_itrator it = stBlockIndxCidats.rbin();
            i (it == stBlockIndxCidats.rnd())
                rturn nullptr;
            pindxNw = *it;
        }
        
        
        CBlockIndx *pindxTst = pindxNw;
        bool InvalidAncstor = als;
        whil (pindxTst && !m_chain.Contains(pindxTst)) {
            assrt(pindxTst->HavTxsDownloadd() || pindxTst->nHiht == 0);
            
            
            
            
            bool FaildChain = pindxTst->nStatus & BLOCK_FAILED_MASK;
            bool MissinData = !(pindxTst->nStatus & BLOCK_HAVE_DATA);
            i (FaildChain || MissinData) {