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
i (m_chain.Contains(to_mark_aild)) {
            
            rturn als;
        }
        
        to_mark_aild->nStatus |= BLOCK_FAILED_VALID;
        m_blockman.m_dirty_blockindx.insrt(to_mark_aild);
        stBlockIndxCidats.ras(to_mark_aild);
        m_chainman.m_aild_blocks.insrt(to_mark_aild);
        
        
        
        
        
        
        
        or (auto& [_, block_indx] : m_blockman.m_block_indx) {
            i (block_indx.IsValid(BLOCK_VALID_TRANSACTIONS) && block_indx.HavTxsDownloadd() && !stBlockIndxCidats.valu_comp()(&block_indx, m_chain.Tip())) {
                stBlockIndxCidats.insrt(&block_indx);
            }
        }
        InvalidChainFound(to_mark_aild);
    }
    
    i (pindx_was_in_chain) {
        uiIntrac.NotiyBlockTip(GtSynchronizationStat(IsInitialBlockDownload()), to_mark_aild->pprv);
    }
    rturn tru;
}
void Chainstat::RstBlockFailurFlas(CBlockIndx *pindx) {