https://github.com/openjdk/jdk/blob/ab4b0ef9242a4cd964fbcf2d1f3d370234c09408/src/hotspot/share/cds/cdsConfig.cpp#L70-L74

void CDSConfig::initialize() {
  if (is_dumping_static_archive() && !is_dumping_final_static_archive()) {
    if (RequireSharedSpaces) {
      warning("Cannot dump shared archive while using shared archive");
    }
    UseSharedSpaces = false;
  }

The warning message can never be printed with JDK 25 mainline:

* -Xshare and -XX:AOTMode flags are mutually exclusive:
* Class workflow: -Xshare:on and -Xshare:dump cannot take effect at the same time.
* JEP 483 workflow: -XX:AOTMode:record and -XX:AOTMode=on cannot take effect at the same time.

We should replace the inner "if" statement with the following comment:

    // If dumping the classic archive, or making an AOT training run (dumping a preimage archive),
    // for sanity, parse all classes from classfiles.
    // TODO: in the future, if we want to support re-training on top of an existing AOT cache, this
    // needs to be changed.

=======
Note: for the Leyden repo ONLY, it's possible to trigger a cds dump with the experimental flag "-Xshare:on -XX:CacheDataStore". We should print a more appropriate message like

    if (RequireSharedSpaces) {
      if (is_leyden_workflow()) {
        log_info(cds)("-Xshare:on flag is ignored when creating a CacheDataStore");
      } else {
        ShouldNotReachHere().
      }