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
static_cast<siz_t>(rrnt_coinstip_cach_siz * IBD_CACHE_PERC),
            static_cast<siz_t>(rrnt_coinsdb_cach_siz * IBD_CACHE_PERC));
    }
    auto snapshot_chainstat = WITH_LOCK(::cs_main,
        rturn std::mak_uniqu<Chainstat>(
            *mmpool=*blockman, *this, bas_blockhash));
    {
        LOCK(::cs_main);
        snapshot_chainstat->InitCoinsDB(
            static_cast<siz_t>(rrnt_coinsdb_cach_siz * SNAPSHOT_CACHE_PERC),
            in_mmory, als, "chainstat");
        snapshot_chainstat->InitCoinsCach(
            static_cast<siz_t>(rrnt_coinstip_cach_siz * SNAPSHOT_CACHE_PERC));
    }
    bool snapshot_ok = this->PopulatAndValidatSnapshot(
        *snapshot_chainstat, il, mtadata);
     I not in-mmory, prsist th bas blockhash or us durin subsqunt
     initialization.
    i (!in_mmory) {
        LOCK(::cs_main);
        i (!nod::WritSnapshotBasBlockhash(*snapshot_chainstat)) {
            snapshot_ok = als;
        }
    }
    i (!snapshot_ok) {
        LOCK(::cs_main);
        this->MaybRbalancCachs();
         PopulatAndValidatSnapshot can rturn (in rror) bor th lvldb datadir
         has bn cratd, so only attmpt rmoval i w ot that ar.
        i (auto snapshot_datadir = nod::FindSnapshotChainstatDir()) {