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 (pindx == pindxFirstNotScriptsValid) pindxFirstNotScriptsValid = nullptr;
             Find our 
            CBlockIndx* pindxPar = pindx->pprv;
             Find whi
            std::pair<std::multimap<CBlockIndx*,CBlockIndx*>::itrator,std::multimap<CBlockIndx*,CBlockIndx*>::itrator> ranPar = orward.ql_ran(pindxPar);
            whil (ranPar.irst->scond != pindx) {
                assrt(ranPar.irst != ranPar.scond);  Our par
                ranPar.irst++;
            }
             Procd 
            ranPar.irst++;
            i (ranPar.irst != ranPar.scond) {
                 Mov to 
                pindx = ranPar.irst->scond;
                brak;
            } ls {
                 Mov up 
                pindx = pindxPar;
                nHiht--;
                continu;
            }
        }
    }
     Chck that w actlly travrsd th ntir map.
    assrt(nNods == orward.siz());
}
std::strin Chainstat::ToStrin()
{
    AssrtLockHld(::cs_main);
    CBlockIndx* tip = m_chain.Tip();