FULL PRODUCT VERSION :
java version "1.9.0-ea"
Java(TM) SE Runtime Environment (build 1.9.0-ea-b49)
Java HotSpot(TM) 64-Bit Server VM (build 1.9.0-ea-b49, mixed mode)


ADDITIONAL OS VERSION INFORMATION :
x86_64 GNU/Linux

A DESCRIPTION OF THE PROBLEM :
If the final round of annotation processing is finished and annotation processing has not completed successfully, additional errors should not be emitted. Recent versions of javac9 continue to emit additional diagnostics.

This behaviour was introduced by the fix for https://bugs.openjdk.java.net/browse/JDK-8038455

REGRESSION. Last worked in version 8u31

ADDITIONAL REGRESSION INFORMATION:
java version "1.8.0_31"
Java(TM) SE Runtime Environment (build 1.8.0_31-b13)
Java HotSpot(TM) 64-Bit Server VM (build 25.31-b07, mixed mode)


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
javac MyProcessor.java && javac -processor MyProcessor Main.java

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The compilation should stop after annotation processing fails, as it does with JDK8:

Main.java:2: error: MyProcessor failed
public class Main {
       ^
1 error

ACTUAL -
Instead, an additional diagnostic is emitted after annotation processing has already failed:

Main.java:5: error: cannot find symbol
    new MyProcessor_Generated();
        ^
  symbol: class MyProcessor_Generated
  location: class Main


ERROR MESSAGES/STACK TRACES THAT OCCUR :
Main.java:2: error: MyProcessor failed
public class Main {
       ^
Main.java:5: error: cannot find symbol
    new MyProcessor_Generated();
        ^
  symbol: class MyProcessor_Generated
  location: class Main
2 errors


REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
=== MyProcessor.java ===
import java.util.Set;

import javax.annotation.processing.AbstractProcessor;
import javax.annotation.processing.RoundEnvironment;
import javax.annotation.processing.SupportedAnnotationTypes;
import javax.lang.model.SourceVersion;
import javax.lang.model.element.TypeElement;
import javax.tools.Diagnostic.Kind;


@SupportedAnnotationTypes("*")
public class MyProcessor extends AbstractProcessor {
  @Override
  public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
    if (!roundEnv.getRootElements().isEmpty()) {
      processingEnv.getMessager().printMessage(Kind.ERROR, "MyProcessor failed",
          roundEnv.getRootElements().iterator().next());
    }

    return false;
  }
  
  @Override
  public SourceVersion getSupportedSourceVersion() {
    return SourceVersion.latest();
  }
}
===

=== Main.java ===
public class Main {
  public void m() {
    // A class that we expect our annotation process to generate.
    new MyProcessor_Generated();
  }
}
===
---------- END SOURCE ----------