FULL PRODUCT VERSION :
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)


ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 6.1.7601]

A DESCRIPTION OF THE PROBLEM :
Attached NullPointerException occurs when trying to compile the attached class.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
$ javac Test.java

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
No NPE and compiled class file
ACTUAL -
NPE and no compiled class file

ERROR MESSAGES/STACK TRACES THAT OCCUR :
An exception has occurred in the compiler (1.8.0_31). Please file a bug at the Java Developer Connection (http://java.sun.com/webapps/bugreport)  after checking the Bug Parade for duplicates. Include your program and the following diagnostic in your report.  Thank you.
java.lang.NullPointerException
        at com.sun.tools.javac.code.Types.isConvertible(Types.java:290)
        at com.sun.tools.javac.comp.Check.assertConvertible(Check.java:922)
        at com.sun.tools.javac.comp.Check.checkMethod(Check.java:876)
        at com.sun.tools.javac.comp.Attr.checkMethod(Attr.java:3838)
        at com.sun.tools.javac.comp.Attr.checkIdInternal(Attr.java:3615)
        at com.sun.tools.javac.comp.Attr.checkMethodIdInternal(Attr.java:3522)
        at com.sun.tools.javac.comp.Attr.checkMethodId(Attr.java:3501)
        at com.sun.tools.javac.comp.Attr.checkId(Attr.java:3488)
        at com.sun.tools.javac.comp.Attr.visitSelect(Attr.java:3370)
        at com.sun.tools.javac.tree.JCTree$JCFieldAccess.accept(JCTree.java:1897)
        at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:607)
        at com.sun.tools.javac.comp.Attr.visitApply(Attr.java:1843)
        at com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1465)
        at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:607)
        at com.sun.tools.javac.comp.Attr.attribExpr(Attr.java:649)
        at com.sun.tools.javac.comp.Attr.visitVarDef(Attr.java:1093)
        at com.sun.tools.javac.tree.JCTree$JCVariableDecl.accept(JCTree.java:852)
        at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:607)
        at com.sun.tools.javac.comp.Attr.attribStat(Attr.java:676)
        at com.sun.tools.javac.comp.Attr.attribStats(Attr.java:692)
        at com.sun.tools.javac.comp.Attr.visitBlock(Attr.java:1142)
        at com.sun.tools.javac.tree.JCTree$JCBlock.accept(JCTree.java:909)
        at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:607)
        at com.sun.tools.javac.comp.Attr.attribStat(Attr.java:676)
        at com.sun.tools.javac.comp.Attr.visitMethodDef(Attr.java:1035)
        at com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:778)
        at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:607)
        at com.sun.tools.javac.comp.Attr.attribStat(Attr.java:676)
        at com.sun.tools.javac.comp.Attr.attribClassBody(Attr.java:4342)
        at com.sun.tools.javac.comp.Attr.attribClass(Attr.java:4252)
        at com.sun.tools.javac.comp.Attr.attribClass(Attr.java:4181)
        at com.sun.tools.javac.comp.Attr.attrib(Attr.java:4156)
        at com.sun.tools.javac.main.JavaCompiler.attribute(JavaCompiler.java:1248)
        at com.sun.tools.javac.main.JavaCompiler.compile2(JavaCompiler.java:901)
        at com.sun.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:860)
        at com.sun.tools.javac.main.Main.compile(Main.java:523)
        at com.sun.tools.javac.main.Main.compile(Main.java:381)
        at com.sun.tools.javac.main.Main.compile(Main.java:370)
        at com.sun.tools.javac.main.Main.compile(Main.java:361)
        at com.sun.tools.javac.Main.compile(Main.java:56)
        at com.sun.tools.javac.Main.main(Main.java:42)


REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;

public class Test {

    public static void main(String[] args) {
        // not my real initialization code, just for illustration purposes
        List<AtomicInteger> values = new ArrayList<>();
        for(int i = 0; i < 10; i++) {
            values.add(new AtomicInteger());
        }

        // this is the problematic reduce
        int total = values
                .parallelStream()
                .reduce(0,
                        (currentValue, currentAtomic)
                                -> currentValue + currentAtomic.get(),
                        (combiner1, combiner2) -> combiner1 + combiner2);
    }
}

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

CUSTOMER SUBMITTED WORKAROUND :
Pulling the declaration of the lambdas out of the method call seems to work fine as shown here: http://stackoverflow.com/questions/28827784/java-8-compiler-bug-with-stream-and-reduce/28827927#28827927