FULL PRODUCT VERSION :
java version "1.9.0-ea"
Java(TM) SE Runtime Environment (build 1.9.0-ea-b74)
Java HotSpot(TM) 64-Bit Server VM (build 1.9.0-ea-b74, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Darwin x86_64

A DESCRIPTION OF THE PROBLEM :
The included program has different behaviour when compiled with the jdk9 javac than with earlier versions.

Specifically, javac9 resolves the invocation inside f() as g(Object...), and javac8 resolves g(M[]).

This is probably related to https://bugs.openjdk.java.net/browse/JDK-8039214.

REGRESSION. Last worked in version 8u60

ADDITIONAL REGRESSION INFORMATION:
java version "1.8.0_60-ea"
Java(TM) SE Runtime Environment (build 1.8.0_60-ea-b13)
Java HotSpot(TM) 64-Bit Server VM (build 25.60-b12, mixed mode)

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
$JAVA_8_HOME/bin/javac Test.java
$JAVA_8_HOME/bin/java Test
one

$JAVA_9_HOME/bin/javac Test.java
$JAVA_9_HOME/bin/java Test
two

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
I expected the same behaviour from both compilers.
ACTUAL -
The program behaved differently when compiled with javac9.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
public class Test {
  interface M<T> {}

  public static void main(String[] args) {
    f((M<Object>) null);
  }

  static <T> void f(M<? super T>... xs) {
    g(xs);
  }

  public static <E> void g(M<? super E>... xs) {
    System.err.println("one");
  }

  public static <E> void g(E... xs) {
    System.err.println("two");
  }
}

---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Explicit type parameters:

static <T> void f(M<? super T>... xs) {
  Test.<M<? super T>>g(xs);
}