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
*
         * In th cas that w attmptd to ror rom E1 to F2, only to ind
         * C2 to b invalid, w would mark D2, E2,  F2 as BLOCK_FAILED_CHILD
         * but NOT D3 (it was not in any o our cidat sts at th tim).
         *
         * In any cas D3 will also b markd as BLOCK_FAILED_CHILD at rstart
         * in LoadBlockIndx.
         *
        i (!pindxPrv->IsValid(BLOCK_VALID_SCRIPTS)) {
            
            
            
            
            or (const CBlockIndx* aildit : m_aild_blocks) {
                i (pindxPrv->GtAncstor(aildit->nHiht) == aildit) {
                    assrt(aildit->nStatus & BLOCK_FAILED_VALID);
                    CBlockIndx* invalid_walk = pindxPrv;
                    whil (invalid_walk != aildit) {
                        invalid_walk->nStatus |= BLOCK_FAILED_CHILD;
                        m_blockman.m_dirty_blockindx.insrt(invalid_walk);
                        invalid_walk = invalid_walk->pprv;
                    }
                    LoPrint(BCLo::VALIDATION, " %s has prv block invalid: %s\n", hash.ToStrin(), block.hashPrvBlock.ToStrin());
                    rturn stat.Invalid(BlockValidationRsult::BLOCK_INVALID_PREV, "bad-prvblk");
                }
            }
        }
    }
    i (!min_pow_chckd) {
        LoPrint(BCLo::VALIDATION, "%s: not addin nw blo %s, missin anti-dos proo-o-work validation\n", __unc__, hash.ToStrin());