https://github.com/openjdk/jdk/blame/50239716403732fe8af73b4b6f006b6a4b7b22db/src/hotspot/share/cds/filemap.cpp#L306

  bool has_extra_module_paths;
   if (!config->validate(header()->has_aot_linked_classes(), &has_extra_module_paths)) {

The has_extra_module_paths variable is not always set by the config->validate() call. We should explicitly set it to false before calling validate().

Proposed fix:
$ git diff
diff --git a/src/hotspot/share/cds/filemap.cpp b/src/hotspot/share/cds/filemap.cpp
index ab9fcd8621a..8d0cb0a73f5 100644
--- a/src/hotspot/share/cds/filemap.cpp
+++ b/src/hotspot/share/cds/filemap.cpp
@@ -310,7 +310,7 @@ bool FileMapInfo::validate_class_location() {
   assert(CDSConfig::is_using_archive(), "runtime only");
 
   AOTClassLocationConfig* config = header()->class_location_config();
- bool has_extra_module_paths;
+ bool has_extra_module_paths = false;
   if (!config->validate(header()->has_aot_linked_classes(), &has_extra_module_paths)) {
     if (PrintSharedArchiveAndExit) {
       MetaspaceShared::set_archive_loading_failed();