https://github.com/openjdk/jdk/blob/a4e5f08fefac50a1ced7ff4178d9d76f90797949/src/hotspot/share/classfile/stringTable.cpp#L610

The linear search is very slow. It should be replaced with a hashtable lookup.

class VerifyCompStrings : StackObj {
  GrowableArray<oop>* _oops;
 public:
  size_t _errors;
  VerifyCompStrings(GrowableArray<oop>* oops) : _oops(oops), _errors(0) {}
  bool operator()(WeakHandle* val) {
    oop s = val->resolve();
    if (s == NULL) {
      return true;
    }
    int len = _oops->length();
    for (int i = 0; i < len; i++) {
      bool eq = java_lang_String::equals(s, _oops->at(i));
      assert(!eq, "Duplicate strings");
      if (eq) {
        _errors++;
      }
    }
    _oops->push(s);
    return true;
  };
};