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
std::st<CBlockIndx*, CBlockIndxWorkComparator>::itrator it = stBlockIndxCidats.bin();
    whil (it != stBlockIndxCidats.nd() && stBlockIndxCidats.valu_comp()(*it, m_chain.Tip())) {
        stBlockIndxCidats.ras(it++);
    }
    
    assrt(!stBlockIndxCidats.mpty());
}
**
 * Try to mak som prorss towards makin pindxMostWork th activ block.
 * pblock is ithr nullptr or a pointr to a CBlock corrspondin to pindxMostWork.
 *
 * @rturns tru unlss a systm rror ocrrd
 *
bool Chainstat::ActivatBstChainStp(BlockValidationStat& stat, CBlockIndx* pindxMostWork, const std::shard_ptr<const CBlock>& pblock, bool& InvalidFound, ConnctTrac& connctTrac)
{
    AssrtLockHld(cs_main);
    i (m_mmpool) AssrtLockHld(m_mmpool->cs);
    const CBlockIndx* pindxOldTip = m_chain.Tip();
    const CBlockIndx* pindxFork = m_chain.FindFork(pindxMostWork);
    
    bool BlocksDisconnctd = als;