Sure, I cutted it because is quite long:
[ERROR] java.util.concurrent.ExecutionException: java.lang.RuntimeException: error loading marshalling extension: org.jboss.errai.enterprise.rebind.ObserversMarshallingExtension
[ERROR] at java.util.concurrent.FutureTask.report(FutureTask.java:122)
[ERROR] at java.util.concurrent.FutureTask.get(FutureTask.java:188)
[ERROR] at org.jboss.errai.config.rebind.AsyncGenerators$FutureWrapper.get(AsyncGenerators.java:112)
[ERROR] at org.jboss.errai.config.rebind.AsyncGenerators$FutureWrapper.get(AsyncGenerators.java:86)
[ERROR] at org.jboss.errai.config.rebind.AbstractAsyncGenerator.startAsyncGeneratorsAndWaitFor(AbstractAsyncGenerator.java:100)
[ERROR] at org.jboss.errai.marshalling.rebind.MarshallersGenerator.generate(MarshallersGenerator.java:221)
[ERROR] at com.google.gwt.core.ext.IncrementalGenerator.generateNonIncrementally(IncrementalGenerator.java:40)
[ERROR] at com.google.gwt.dev.javac.StandardGeneratorContext.runGeneratorIncrementally(StandardGeneratorContext.java:676)
[ERROR] at com.google.gwt.dev.cfg.RuleGenerateWith.realize(RuleGenerateWith.java:41)
[ERROR] at com.google.gwt.dev.shell.StandardRebindOracle$Rebinder.rebind(StandardRebindOracle.java:79)
[ERROR] at com.google.gwt.dev.shell.StandardRebindOracle.rebind(StandardRebindOracle.java:276)
[ERROR] at com.google.gwt.dev.shell.StandardRebindOracle.rebind(StandardRebindOracle.java:265)
[ERROR] at com.google.gwt.dev.DistillerRebindPermutationOracle.getAllPossibleRebindAnswers(DistillerRebindPermutationOracle.java:91)
[ERROR] at com.google.gwt.dev.jjs.impl.UnifyAst$UnifyVisitor.handleGwtCreate(UnifyAst.java:387)
[ERROR] at com.google.gwt.dev.jjs.impl.UnifyAst$UnifyVisitor.handleMagicMethodCall(UnifyAst.java:465)
[ERROR] at com.google.gwt.dev.jjs.impl.UnifyAst$UnifyVisitor.endVisit(UnifyAst.java:255)
[ERROR] at com.google.gwt.dev.jjs.ast.JMethodCall.traverse(JMethodCall.java:244)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.traverse(JModVisitor.java:361)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.accept(JModVisitor.java:273)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.accept(JModVisitor.java:265)
[ERROR] at com.google.gwt.dev.jjs.ast.JVisitor.accept(JVisitor.java:117)
[ERROR] at com.google.gwt.dev.jjs.ast.JCastOperation.traverse(JCastOperation.java:65)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.traverse(JModVisitor.java:361)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.accept(JModVisitor.java:273)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.accept(JModVisitor.java:265)
[ERROR] at com.google.gwt.dev.jjs.ast.JVisitor.accept(JVisitor.java:117)
[ERROR] at com.google.gwt.dev.jjs.ast.JBinaryOperation.traverse(JBinaryOperation.java:81)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.traverse(JModVisitor.java:361)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.accept(JModVisitor.java:273)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.accept(JModVisitor.java:265)
[ERROR] at com.google.gwt.dev.jjs.ast.JVisitor.accept(JVisitor.java:117)
[ERROR] at com.google.gwt.dev.jjs.ast.JExpressionStatement.traverse(JExpressionStatement.java:41)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor$ListContextImmutable.traverse(JModVisitor.java:170)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.acceptWithInsertRemoveImmutable(JModVisitor.java:336)
[ERROR] at com.google.gwt.dev.jjs.ast.JBlock.traverse(JBlock.java:83)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor$ListContextImmutable.traverse(JModVisitor.java:170)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.acceptWithInsertRemoveImmutable(JModVisitor.java:336)
[ERROR] at com.google.gwt.dev.jjs.ast.JBlock.traverse(JBlock.java:83)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.traverse(JModVisitor.java:361)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.accept(JModVisitor.java:273)
[ERROR] at com.google.gwt.dev.jjs.ast.JVisitor.accept(JVisitor.java:138)
[ERROR] at com.google.gwt.dev.jjs.ast.JVisitor.accept(JVisitor.java:134)
[ERROR] at com.google.gwt.dev.jjs.ast.JMethodBody.traverse(JMethodBody.java:82)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.traverse(JModVisitor.java:361)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.accept(JModVisitor.java:273)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.accept(JModVisitor.java:265)
[ERROR] at com.google.gwt.dev.jjs.ast.JMethod.visitChildren(JMethod.java:449)
[ERROR] at com.google.gwt.dev.jjs.ast.JMethod.traverse(JMethod.java:418)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.traverse(JModVisitor.java:361)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.accept(JModVisitor.java:273)
[ERROR] at com.google.gwt.dev.jjs.ast.JModVisitor.accept(JModVisitor.java:265)
[ERROR] at com.google.gwt.dev.jjs.impl.UnifyAst.mainLoop(UnifyAst.java:940)
[ERROR] at com.google.gwt.dev.jjs.impl.UnifyAst.exec(UnifyAst.java:665)
[ERROR] at com.google.gwt.dev.jjs.JavaToJavaScriptCompiler.precompile(JavaToJavaScriptCompiler.java:672)
[ERROR] at com.google.gwt.dev.jjs.JavaScriptCompiler.precompile(JavaScriptCompiler.java:34)
[ERROR] at com.google.gwt.dev.Precompile.precompile(Precompile.java:271)
[ERROR] at com.google.gwt.dev.Precompile.precompile(Precompile.java:223)
[ERROR] at com.google.gwt.dev.Precompile.precompile(Precompile.java:139)
[ERROR] at com.google.gwt.dev.Compiler.run(Compiler.java:167)
[ERROR] at com.google.gwt.dev.codeserver.Recompiler.compile(Recompiler.java:115)
[ERROR] at com.google.gwt.dev.codeserver.ModuleState.<init>(ModuleState.java:58)
[ERROR] at com.google.gwt.dev.codeserver.CodeServer.makeModules(CodeServer.java:120)
[ERROR] at com.google.gwt.dev.codeserver.CodeServer.start(CodeServer.java:95)
[ERROR] at com.google.gwt.dev.codeserver.CodeServer.main(CodeServer.java:71)
[ERROR] at com.google.gwt.dev.codeserver.CodeServer.main(CodeServer.java:49)
[ERROR] Caused by: java.lang.RuntimeException: error loading marshalling extension: org.jboss.errai.enterprise.rebind.ObserversMarshallingExtension
[ERROR] at org.jboss.errai.marshalling.rebind.MarshallerGeneratorFactory._generate(MarshallerGeneratorFactory.java:206)
[ERROR] at org.jboss.errai.marshalling.rebind.MarshallerGeneratorFactory.generate(MarshallerGeneratorFactory.java:147)
[ERROR] at org.jboss.errai.marshalling.rebind.MarshallersGenerator.generate(MarshallersGenerator.java:242)
[INFO] [ERROR] Error generating MarshallerFactoryImpl
[ERROR] at org.jboss.errai.config.rebind.AbstractAsyncGenerator$1.call(AbstractAsyncGenerator.java:43)
[ERROR] at org.jboss.errai.config.rebind.AbstractAsyncGenerator$1.call(AbstractAsyncGenerator.java:40)
[ERROR] at java.util.concurrent.FutureTask.run(FutureTask.java:262)
[INFO] [ERROR] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
[ERROR] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
[ERROR] at java.lang.Thread.run(Thread.java:744)
[ERROR] Caused by: java.lang.IllegalArgumentException: Unable to load class "org.jboss.errai.marshalling.server.impl.ServerMarshallingFactoryImpl"
[ERROR] at org.jboss.errai.reflections.ReflectionUtils.forName(ReflectionUtils.java:148)
[ERROR] at org.jboss.errai.reflections.ReflectionUtils.forNames(ReflectionUtils.java:157)
[ERROR] at org.jboss.errai.reflections.Reflections.getTypesAnnotatedWith(Reflections.java:395)
[ERROR] at org.jboss.errai.common.metadata.MetaDataScanner.getTypesAnnotatedWith(MetaDataScanner.java:287)
[ERROR] at org.jboss.errai.enterprise.rebind.ObserversMarshallingExtension.scanForObserverPointsInClassPath(ObserversMarshallingExtension.java:88)
[ERROR] at org.jboss.errai.enterprise.rebind.ObserversMarshallingExtension.configure(ObserversMarshallingExtension.java:57)
[ERROR] at org.jboss.errai.marshalling.rebind.MarshallerGeneratorFactory._generate(MarshallerGeneratorFactory.java:203)
[ERROR] ... 8 more