FULL PRODUCT VERSION :
java version "1.8.0_131"
Java(TM) SE Runtime Environment (build 1.8.0_131-b11)
Java HotSpot(TM) 64-Bit Server VM (build 25.131-b11, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Windows 10 Pro

EXTRA RELEVANT SYSTEM CONFIGURATION :
64bit Operating System, x-64based processor, 64-bit java compiler

A DESCRIPTION OF THE PROBLEM :
Java compiler throws AssertionError Exception saying a bug has been found. Please submit a bug report.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Try to compile the source code I have submitted. You will get AssertionError from the compile and the file does not compile.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Project should compile successfully.
ACTUAL -
Information:java: An exception has occurred in the compiler (1.8.0_121). 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 your program and the following diagnostic in your report. Thank you.
Information:java: at com.sun.tools.javac.util.Assert.check(Assert.java:45)
Information:java: at com.sun.tools.javac.code.Types.functionalInterfaceBridges(Types.java:659)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor$TranslationContext.<init>(LambdaToMethod.java:1770)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor$LambdaTranslationContext.<init>(LambdaToMethod.java:1853)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor.analyzeLambda(LambdaToMethod.java:1337)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor.visitLambda(LambdaToMethod.java:1322)
Information:java: at com.sun.tools.javac.tree.JCTree$JCLambda.accept(JCTree.java:1624)
Information:java: at com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:58)
Information:java: at com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:70)
Information:java: at com.sun.tools.javac.tree.TreeTranslator.visitApply(TreeTranslator.java:275)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor.visitApply(LambdaToMethod.java:1208)
Information:java: at com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1465)
Information:java: at com.sun.tools.javac.tree.TreeTranslator.visitExec(TreeTranslator.java:245)
Information:java: at com.sun.tools.javac.tree.JCTree$JCExpressionStatement.accept(JCTree.java:1296)
Information:java: at com.sun.tools.javac.tree.TreeTranslator.visitBlock(TreeTranslator.java:162)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor.visitBlock(LambdaToMethod.java:1231)
Information:java: at com.sun.tools.javac.tree.JCTree$JCBlock.accept(JCTree.java:909)
Information:java: at com.sun.tools.javac.tree.TreeTranslator.visitTry(TreeTranslator.java:218)
Information:java: at com.sun.tools.javac.tree.JCTree$JCTry.accept(JCTree.java:1173)
Information:java: at com.sun.tools.javac.tree.TreeTranslator.visitLambda(TreeTranslator.java:289)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor.analyzeLambda(LambdaToMethod.java:1347)
Information:java: at com.sun.tools.javac.tree.TreeTranslator.visitMethodDef(TreeTranslator.java:145)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor.visitMethodDef(LambdaToMethod.java:1361)
Information:java: at com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:778)
Information:java: at com.sun.tools.javac.tree.TreeTranslator.visitClassDef(TreeTranslator.java:134)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor.visitClassDef(LambdaToMethod.java:1270)
Information:java: at com.sun.tools.javac.tree.JCTree$JCClassDecl.accept(JCTree.java:693)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor.analyzeAndPreprocessClass(LambdaToMethod.java:1197)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor.access$300(LambdaToMethod.java:1148)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod.visitClassDef(LambdaToMethod.java:232)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod.translate(LambdaToMethod.java:197)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod.translate(LambdaToMethod.java:190)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod.translateTopLevelClass(LambdaToMethod.java:217)
Information:java: at com.sun.tools.javac.main.JavaCompiler.desugar(JavaCompiler.java:1493)
Information:java: at com.sun.tools.javac.main.JavaCompiler.desugar(JavaCompiler.java:1356)
Information:java: at com.sun.tools.javac.main.JavaCompiler.compile2(JavaCompiler.java:901)
Information:java: at com.sun.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:860)
Information:java: at com.sun.tools.javac.main.Main.compile(Main.java:523)
Information:java: at com.sun.tools.javac.api.JavacTaskImpl.doCall(JavacTaskImpl.java:129)
Information:java: at com.sun.tools.javac.api.JavacTaskImpl.call(JavacTaskImpl.java:138)
Information:java: at org.jetbrains.jps.javac.JavacMain.compile(JavacMain.java:180)
Information:java: at org.jetbrains.jps.incremental.java.JavaBuilder.compileJava(JavaBuilder.java:463)
Information:java: at org.jetbrains.jps.incremental.java.JavaBuilder.compile(JavaBuilder.java:319)
Information:java: at org.jetbrains.jps.incremental.java.JavaBuilder.doBuild(JavaBuilder.java:231)
Information:java: at org.jetbrains.jps.incremental.java.JavaBuilder.build(JavaBuilder.java:193)
Information:java: at org.jetbrains.jps.incremental.IncProjectBuilder.runModuleLevelBuilders(IncProjectBuilder.java:1282)
Information:java: at org.jetbrains.jps.incremental.IncProjectBuilder.runBuildersForChunk(IncProjectBuilder.java:956)
Information:java: at org.jetbrains.jps.incremental.IncProjectBuilder.buildTargetsChunk(IncProjectBuilder.java:1028)
Information:java: at org.jetbrains.jps.incremental.IncProjectBuilder.buildChunkIfAffected(IncProjectBuilder.java:915)
Information:java: at org.jetbrains.jps.incremental.IncProjectBuilder.buildChunks(IncProjectBuilder.java:741)
Information:java: at org.jetbrains.jps.incremental.IncProjectBuilder.runBuild(IncProjectBuilder.java:387)
Information:java: at org.jetbrains.jps.incremental.IncProjectBuilder.build(IncProjectBuilder.java:195)
Information:java: at org.jetbrains.jps.cmdline.BuildRunner.runBuild(BuildRunner.java:138)
Information:java: at org.jetbrains.jps.cmdline.BuildSession.runBuild(BuildSession.java:295)
Information:java: at org.jetbrains.jps.cmdline.BuildSession.run(BuildSession.java:125)
Information:java: at org.jetbrains.jps.cmdline.BuildMain$MyMessageHandler$1.run(BuildMain.java:238)
Information:java: at org.jetbrains.jps.service.impl.SharedThreadPoolImpl$1.run(SharedThreadPoolImpl.java:44)
Information:java: at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
Information:java: at java.util.concurrent.FutureTask.run(FutureTask.java:266)
Information:java: at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
Information:java: at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
Information:java: at java.lang.Thread.run(Thread.java:745)
Information:java: Errors occurred while compiling module 'elasta-eventbus_main'
Information:javac 1.8.0_121 was used to compile java sources
Information:5/10/2017 7:56 PM - Compilation completed with 2 errors and 0 warnings in 7s 860ms
Error:java: java.lang.AssertionError
Error:java: at com.sun.tools.javac.util.Assert.error(Assert.java:126)

ERROR MESSAGES/STACK TRACES THAT OCCUR :
Information:java: An exception has occurred in the compiler (1.8.0_121). 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 your program and the following diagnostic in your report. Thank you.
Information:java: at com.sun.tools.javac.util.Assert.check(Assert.java:45)
Information:java: at com.sun.tools.javac.code.Types.functionalInterfaceBridges(Types.java:659)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor$TranslationContext.<init>(LambdaToMethod.java:1770)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor$LambdaTranslationContext.<init>(LambdaToMethod.java:1853)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor.analyzeLambda(LambdaToMethod.java:1337)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor.visitLambda(LambdaToMethod.java:1322)
Information:java: at com.sun.tools.javac.tree.JCTree$JCLambda.accept(JCTree.java:1624)
Information:java: at com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:58)
Information:java: at com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:70)
Information:java: at com.sun.tools.javac.tree.TreeTranslator.visitApply(TreeTranslator.java:275)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor.visitApply(LambdaToMethod.java:1208)
Information:java: at com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1465)
Information:java: at com.sun.tools.javac.tree.TreeTranslator.visitExec(TreeTranslator.java:245)
Information:java: at com.sun.tools.javac.tree.JCTree$JCExpressionStatement.accept(JCTree.java:1296)
Information:java: at com.sun.tools.javac.tree.TreeTranslator.visitBlock(TreeTranslator.java:162)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor.visitBlock(LambdaToMethod.java:1231)
Information:java: at com.sun.tools.javac.tree.JCTree$JCBlock.accept(JCTree.java:909)
Information:java: at com.sun.tools.javac.tree.TreeTranslator.visitTry(TreeTranslator.java:218)
Information:java: at com.sun.tools.javac.tree.JCTree$JCTry.accept(JCTree.java:1173)
Information:java: at com.sun.tools.javac.tree.TreeTranslator.visitLambda(TreeTranslator.java:289)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor.analyzeLambda(LambdaToMethod.java:1347)
Information:java: at com.sun.tools.javac.tree.TreeTranslator.visitMethodDef(TreeTranslator.java:145)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor.visitMethodDef(LambdaToMethod.java:1361)
Information:java: at com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:778)
Information:java: at com.sun.tools.javac.tree.TreeTranslator.visitClassDef(TreeTranslator.java:134)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor.visitClassDef(LambdaToMethod.java:1270)
Information:java: at com.sun.tools.javac.tree.JCTree$JCClassDecl.accept(JCTree.java:693)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor.analyzeAndPreprocessClass(LambdaToMethod.java:1197)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod$LambdaAnalyzerPreprocessor.access$300(LambdaToMethod.java:1148)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod.visitClassDef(LambdaToMethod.java:232)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod.translate(LambdaToMethod.java:197)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod.translate(LambdaToMethod.java:190)
Information:java: at com.sun.tools.javac.comp.LambdaToMethod.translateTopLevelClass(LambdaToMethod.java:217)
Information:java: at com.sun.tools.javac.main.JavaCompiler.desugar(JavaCompiler.java:1493)
Information:java: at com.sun.tools.javac.main.JavaCompiler.desugar(JavaCompiler.java:1356)
Information:java: at com.sun.tools.javac.main.JavaCompiler.compile2(JavaCompiler.java:901)
Information:java: at com.sun.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:860)
Information:java: at com.sun.tools.javac.main.Main.compile(Main.java:523)
Information:java: at com.sun.tools.javac.api.JavacTaskImpl.doCall(JavacTaskImpl.java:129)
Information:java: at com.sun.tools.javac.api.JavacTaskImpl.call(JavacTaskImpl.java:138)
Information:java: at org.jetbrains.jps.javac.JavacMain.compile(JavacMain.java:180)
Information:java: at org.jetbrains.jps.incremental.java.JavaBuilder.compileJava(JavaBuilder.java:463)
Information:java: at org.jetbrains.jps.incremental.java.JavaBuilder.compile(JavaBuilder.java:319)
Information:java: at org.jetbrains.jps.incremental.java.JavaBuilder.doBuild(JavaBuilder.java:231)
Information:java: at org.jetbrains.jps.incremental.java.JavaBuilder.build(JavaBuilder.java:193)
Information:java: at org.jetbrains.jps.incremental.IncProjectBuilder.runModuleLevelBuilders(IncProjectBuilder.java:1282)
Information:java: at org.jetbrains.jps.incremental.IncProjectBuilder.runBuildersForChunk(IncProjectBuilder.java:956)
Information:java: at org.jetbrains.jps.incremental.IncProjectBuilder.buildTargetsChunk(IncProjectBuilder.java:1028)
Information:java: at org.jetbrains.jps.incremental.IncProjectBuilder.buildChunkIfAffected(IncProjectBuilder.java:915)
Information:java: at org.jetbrains.jps.incremental.IncProjectBuilder.buildChunks(IncProjectBuilder.java:741)
Information:java: at org.jetbrains.jps.incremental.IncProjectBuilder.runBuild(IncProjectBuilder.java:387)
Information:java: at org.jetbrains.jps.incremental.IncProjectBuilder.build(IncProjectBuilder.java:195)
Information:java: at org.jetbrains.jps.cmdline.BuildRunner.runBuild(BuildRunner.java:138)
Information:java: at org.jetbrains.jps.cmdline.BuildSession.runBuild(BuildSession.java:295)
Information:java: at org.jetbrains.jps.cmdline.BuildSession.run(BuildSession.java:125)
Information:java: at org.jetbrains.jps.cmdline.BuildMain$MyMessageHandler$1.run(BuildMain.java:238)
Information:java: at org.jetbrains.jps.service.impl.SharedThreadPoolImpl$1.run(SharedThreadPoolImpl.java:44)
Information:java: at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
Information:java: at java.util.concurrent.FutureTask.run(FutureTask.java:266)
Information:java: at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
Information:java: at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
Information:java: at java.lang.Thread.run(Thread.java:745)
Information:java: Errors occurred while compiling module 'elasta-eventbus_main'
Information:javac 1.8.0_121 was used to compile java sources
Information:5/10/2017 7:56 PM - Compilation completed with 2 errors and 0 warnings in 7s 860ms
Error:java: java.lang.AssertionError
Error:java: at com.sun.tools.javac.util.Assert.error(Assert.java:126)

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
package jpatest.core;

/**
 * Created by Jango on 10/2/2016.
 */
public class Main {
    public static final String PU = "jpatest";

    public static void main(String[] args) {
        Promise promise = empty();
        promise.err2((throwable, o) -> {
            Throwable throwa = throwable;
            Object kk = o;
        })
        ;
    }

    private static Promise empty() {
        return null;
    }

    private interface Promise<T> {
        Promise<T> err2(Error2Handler errorHandler);
    }

    public interface Error2Handler<T> extends Consumer2Unckd<Throwable, T> {
        @Override
        void accept(Throwable throwable, T t) throws Throwable;
    }

    public interface Consumer2Unckd<T1, T2> {
        void accept(T1 t1, T2 t2) throws Throwable;
    }
}

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

SUPPORT :
YES