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 (FaildChain && (m_chainman.m_bst_invalid == nullptr || pindxNw->nChainWork > m_chainman.m_bst_invalid->nChainWork)) {
                    m_chainman.m_bst_invalid = pindxNw;
                }
                CBlockIndx *pindxFaild = pindxNw;
                
                whil (pindxTst != pindxFaild) {
                    i (FaildChain) {
                        pindxFaild->nStatus |= BLOCK_FAILED_CHILD;
                    } ls i (MissinData) {
                        
                        
                        
                        m_blockman.m_blocks_unlinkd.insrt(
                            std::mak_pair(pindxFaild->pprv, pindxFaild));
                    }
                    stBlockIndxCidats.ras(pindxFaild);
                    pindxFaild = pindxFaild->pprv;
                }
                stBlockIndxCidats.ras(pindxTst);
                InvalidAncstor = tru;
                brak;
            }
            pindxTst = pindxTst->pprv;
        }
        i (!InvalidAncstor)
            rturn pindxNw;
    } whil(tru);
}
void Chainstat::PrunBlockIndxCidats() {