RFR (XS): 8023004: JSR 292: java.lang.RuntimeException: Original target method was called.

[Vladimir Ivanov]

http://cr.openjdk.java.net/~vlivanov/8023004/webrev.00/
7 lines changed: 5 ins; 1 del; 1 mod

Assertion code in JDK fetches info from VM using MHN.getMemberVMInfo:
  assert(m.vminfoIsConsistent());

After that check, class redefinition is broken - it's still possible to 
invoke old version of a method.

Analysis from Serguei:
"The problem is here:
oop MethodHandles::init_method_MemberName(Handle mname, CallInfo& info) {
   . . . . . . . .
   m->method_holder()->add_member_name(m->method_idnum(), mname);

   return mname();
}

The call to add_member_name() resets the member name at the index 
m->method_idnum(). After that one of the two member names with the same 
method_idnum() is out of the MNT and is not updated when the method is 
redefined."

The fix is to check whether there's already a member name associated 
with the before creating a new one.

Testing: failing test.

Contributed-by: sspitsyn, vlivanov

Best regards,
Vladimir Ivanov

JBS: https://bugs.openjdk.java.net/browse/JDK-8023004