For the case when C2 inlines through MH.linkTo*/invokeBasic adapters (JDK-8072008), attached method should be used, since bytecode information is inaccurate. But nmethod::preserve_callee_argument_oops doesn't do that. For MH.linkTo* case it means stack scanning tries to extract appendix MemberName argument, but generated code omits pushing it on stack. It usually leads to a crash later in GC when garbage oop is dereferenced.