A DESCRIPTION OF THE PROBLEM :
The test method fails to compile, as javac believes that getter.get() returns just Object:

class Scratch {
    static abstract class Getters<T> {
        abstract class Getter {
            abstract T get();
        }
    }

    static class Usage<T, G extends Getters<T>> {
        public T test(G.Getter getter) {
            return getter.get();
        }
    }
}


FREQUENCY : always

If we merely address the issue in allparams() (as in the new backed-off 8343580), the test method compiles, but the emitted signature is as if it was T test(Scratch.Getters.Getter getter), where the Getter inner class appears as a raw type.

For the attached test on 25 mainline JDK as of 2025 May 23, this fails compilation with such a message:

TypeVarInners.java:11: error: incompatible types: TypeVarInners.Base cannot be converted to S
return handler.owner();
^
  where S is a type-variable:
    S extends TypeVarInners.Base<S> declared in method <S>getOwner(TypeVarInners.Base.Handler)
1 error
error: compilation failed

Note the method's signature is already wrong in the error message: it should be <S>getOwner(S.Handler)

Note that assembleClassSig independently examines outer to detect whether it is raw or not:

if (outer.allparams().nonEmpty()) {
   // rawOuter detection
   // code that emits generic encl type signature
} else {
   append(externalize(c.flatname));
}