A DESCRIPTION OF THE PROBLEM :
See source code. Not 100% sure on the exact cause.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
javac BadClass.java

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Class compiles without issue.
ACTUAL -
An exception has occurred in the compiler (11.0.2). Please file a bug against the Java compiler via the Java bug reporting page (http://bugreport.java.com) after checking the Bug Database (http://bugs.java.com) for duplicates. Include y
our program and the following diagnostic in your report. Thank you.
java.lang.AssertionError
        at jdk.compiler/com.sun.tools.javac.util.Assert.error(Assert.java:155)
        at jdk.compiler/com.sun.tools.javac.util.Assert.check(Assert.java:46)
        at jdk.compiler/com.sun.tools.javac.comp.DeferredAttr$2$1.setOverloadKind(DeferredAttr.java:172)
        at jdk.compiler/com.sun.tools.javac.comp.ArgumentAttr.visitReference(ArgumentAttr.java:283)
        at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCMemberReference.accept(JCTree.java:2190)
        at jdk.compiler/com.sun.tools.javac.comp.ArgumentAttr.attribArg(ArgumentAttr.java:197)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribTree(Attr.java:653)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribArgs(Attr.java:751)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.visitApply(Attr.java:1997)
        at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1634)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribTree(Attr.java:655)
        at jdk.compiler/com.sun.tools.javac.comp.DeferredAttr.attribSpeculative(DeferredAttr.java:498)
        at jdk.compiler/com.sun.tools.javac.comp.DeferredAttr.attribSpeculative(DeferredAttr.java:481)
        at jdk.compiler/com.sun.tools.javac.comp.ArgumentAttr.lambda$processArg$0(ArgumentAttr.java:220)
        at jdk.compiler/com.sun.tools.javac.comp.ArgumentAttr.processArg(ArgumentAttr.java:242)
        at jdk.compiler/com.sun.tools.javac.comp.ArgumentAttr.processArg(ArgumentAttr.java:219)
        at jdk.compiler/com.sun.tools.javac.comp.ArgumentAttr.visitApply(ArgumentAttr.java:307)
        at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1634)
        at jdk.compiler/com.sun.tools.javac.comp.ArgumentAttr.attribArg(ArgumentAttr.java:197)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribTree(Attr.java:653)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribArgs(Attr.java:751)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.visitApply(Attr.java:1997)
        at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1634)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribTree(Attr.java:655)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.visitReturn(Attr.java:1866)
        at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCReturn.accept(JCTree.java:1546)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribTree(Attr.java:655)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribStat(Attr.java:724)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribStats(Attr.java:743)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.visitLambda(Attr.java:2598)
        at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCLambda.accept(JCTree.java:1807)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribTree(Attr.java:655)
        at jdk.compiler/com.sun.tools.javac.comp.DeferredAttr$4.complete(DeferredAttr.java:374)
        at jdk.compiler/com.sun.tools.javac.comp.DeferredAttr$DeferredType.check(DeferredAttr.java:335)
        at jdk.compiler/com.sun.tools.javac.comp.DeferredAttr$DeferredType.check(DeferredAttr.java:321)
        at jdk.compiler/com.sun.tools.javac.comp.Resolve$MethodResultInfo.check(Resolve.java:1060)
        at jdk.compiler/com.sun.tools.javac.comp.Resolve$4.checkArg(Resolve.java:887)
        at jdk.compiler/com.sun.tools.javac.comp.Resolve$AbstractMethodCheck.argumentsAcceptable(Resolve.java:775)
        at jdk.compiler/com.sun.tools.javac.comp.Resolve$4.argumentsAcceptable(Resolve.java:896)
        at jdk.compiler/com.sun.tools.javac.comp.Infer.instantiateMethod(Infer.java:181)
        at jdk.compiler/com.sun.tools.javac.comp.Resolve.rawInstantiate(Resolve.java:605)
        at jdk.compiler/com.sun.tools.javac.comp.Resolve.checkMethod(Resolve.java:644)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.checkMethod(Attr.java:4120)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.checkIdInternal(Attr.java:3913)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.checkMethodIdInternal(Attr.java:3814)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.checkId(Attr.java:3803)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.visitSelect(Attr.java:3696)
        at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCFieldAccess.accept(JCTree.java:2110)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribTree(Attr.java:655)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.visitApply(Attr.java:2006)
        at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1634)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribTree(Attr.java:655)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.visitReturn(Attr.java:1866)
        at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCReturn.accept(JCTree.java:1546)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribTree(Attr.java:655)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribStat(Attr.java:724)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribStats(Attr.java:743)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.visitBlock(Attr.java:1294)
        at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCBlock.accept(JCTree.java:1020)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribTree(Attr.java:655)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribStat(Attr.java:724)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.visitMethodDef(Attr.java:1098)
        at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:866)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribTree(Attr.java:655)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribStat(Attr.java:724)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribClassBody(Attr.java:4683)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribClass(Attr.java:4574)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attribClass(Attr.java:4503)
        at jdk.compiler/com.sun.tools.javac.comp.Attr.attrib(Attr.java:4448)
        at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.attribute(JavaCompiler.java:1341)
        at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:973)
        at jdk.compiler/com.sun.tools.javac.main.Main.compile(Main.java:311)
        at jdk.compiler/com.sun.tools.javac.main.Main.compile(Main.java:170)
        at jdk.compiler/com.sun.tools.javac.Main.compile(Main.java:57)
        at jdk.compiler/com.sun.tools.javac.Main.main(Main.java:43)



---------- BEGIN SOURCE ----------
import java.util.Arrays;
import java.util.function.BiFunction;
import java.util.function.Function;
import java.util.stream.Stream;

public class BadClass {

    private static Stream<Object> badMethod(final Object object,
                                            final Function<Object, Object>[] objects,
                                            final BiFunction<Object, Object, Object> func) {
        return Arrays.stream(objects)
                .map(o -> {
                    return func.apply(o.toString(), runFunction(object, o::apply));
                });
    }

    public static <T, R> R runFunction(final T object, final Function<T, R> func) {
        return object == null ? null : func.apply(object);
    }
}

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

CUSTOMER SUBMITTED WORKAROUND :
Replacing the 'o::apply' Lambda method reference with 'o -> o.apply' fixes the issue.

FREQUENCY : always