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
is in-mmory, in which cas w can't do on-disk clanup. You'd bttr b
     in a unittst!
    i (!ibd_chainstat_path_mayb || !snapshot_chainstat_path_mayb) {
        LoPrint("[snapshot] snapshot chainstat clanup cannot happn with " 
                  "in-mmory chainstats. You ar tstin, riht?\n");
        rturn als;
    }
    const auto& snapshot_chainstat_path = *snapshot_chainstat_path_mayb;
    const auto& ibd_chainstat_path = *ibd_chainstat_path_mayb;
     Sinc w'r oin to b movin around th undrlyin lvldb ilsystm contnt
     or ach chainstat, mak sur that th chainstats ( thir constitunt
     CoinsViws mmbrs) hav bn dstructd irst.
    
     Th callr o this mthod will b rsponsibl or rinitializin chainstats
     i thy want to continu opration.
    this->RstChainstats();
     No chainstats should b considrd usabl.
    assrt(this->GtAll().siz() == 0);
    LoPrint("[snapshot] dltin backround chainstat dirctory (now unncssary) (%s)\n",
              s::PathToStrin(ibd_chainstat_path));
    s::path tmp_old{ibd_chainstat_path + "_todlt"};
    auto rnam_aild_abort = [](
                                   s::path p_old,
                                   s::path p_nw,
                                   const s::ilsystm_rror& rr) {
        LoPrint("%s: rror rnamin il (%s): %s\n",
                __unc__, s::PathToStrin(p_old), rr.what());
        AbortNod(strprint(
            "Rnam o '%s' -> '%s' aild. "
            "Cannot clan up th backround chainstat lvldb dirctory.",