今天编译项目的时候，突然报错

:app:transformNativeLibsWithStripDebugSymbolForDebug

详细的错误日志：

org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':app:transformNativeLibsWithStripDebugSymbolForDebug'.
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:100)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:70)
    at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:63)
    at org.gradle.api.internal.tasks.execution.ResolveTaskOutputCachingStateExecuter.execute(ResolveTaskOutputCachingStateExecuter.java:54)
    at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:58)
    at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:88)
    at org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter.execute(ResolveTaskArtifactStateTaskExecuter.java:52)
    at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:52)
    at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:54)
    at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:43)
    at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:34)
    at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker$1.run(DefaultTaskGraphExecuter.java:248)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:197)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:107)
    at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:241)
    at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:230)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.processTask(DefaultTaskPlanExecutor.java:124)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.access$200(DefaultTaskPlanExecutor.java:80)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:105)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:99)
    at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.execute(DefaultTaskExecutionPlan.java:625)
    at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.executeWithTask(DefaultTaskExecutionPlan.java:580)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.run(DefaultTaskPlanExecutor.java:99)
    at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:63)
    at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:46)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:55)
    at java.lang.Thread.run(Thread.java:745)
Caused by: org.gradle.process.internal.ExecException: A problem occurred starting process 'command '/Users/yang/Library/Android/sdk/ndk-bundle/toolchains/mips64el-linux-android-4.9/prebuilt/darwin-x86_64/bin/mips64el-linux-android-strip''
    at org.gradle.process.internal.DefaultExecHandle.execExceptionFor(DefaultExecHandle.java:220)
    at org.gradle.process.internal.DefaultExecHandle.setEndStateInfo(DefaultExecHandle.java:204)
    at org.gradle.process.internal.DefaultExecHandle.failed(DefaultExecHandle.java:340)
    at org.gradle.process.internal.ExecHandleRunner.run(ExecHandleRunner.java:86)
    at org.gradle.internal.operations.BuildOperationIdentifierPreservingRunnable.run(BuildOperationIdentifierPreservingRunnable.java:39)
    ... 6 more
Caused by: net.rubygrapefruit.platform.NativeException: Could not start '/Users/yang/Library/Android/sdk/ndk-bundle/toolchains/mips64el-linux-android-4.9/prebuilt/darwin-x86_64/bin/mips64el-linux-android-strip'
    at net.rubygrapefruit.platform.internal.DefaultProcessLauncher.start(DefaultProcessLauncher.java:27)
    at net.rubygrapefruit.platform.internal.WrapperProcessLauncher.start(WrapperProcessLauncher.java:36)
    at org.gradle.process.internal.ExecHandleRunner.run(ExecHandleRunner.java:68)
    ... 7 more
Caused by: java.io.IOException: Cannot run program "/Users/yang/Library/Android/sdk/ndk-bundle/toolchains/mips64el-linux-android-4.9/prebuilt/darwin-x86_64/bin/mips64el-linux-android-strip" (in directory "/Users/yang/AndroidStudioProjects/VPOS/app"): error=2, No such file or directory
    at java.lang.ProcessBuilder.start(ProcessBuilder.java:1048)
    at net.rubygrapefruit.platform.internal.DefaultProcessLauncher.start(DefaultProcessLauncher.java:25)
    ... 9 more
Caused by: java.io.IOException: error=2, No such file or directory
    at java.lang.UNIXProcess.forkAndExec(Native Method)
    at java.lang.UNIXProcess.<init>(UNIXProcess.java:247)
    at java.lang.ProcessImpl.start(ProcessImpl.java:134)
    at java.lang.ProcessBuilder.start(ProcessBuilder.java:1029)
    ... 10 more

经过查看，发现是缺少了以下文件：

  /Users/yang/Library/Android/sdk/ndk-bundle/toolchains/mips64el-linux-android-4.9/prebuilt/darwin-x86_64/bin/mips64el-linux-android-strip

这个目录是ndk预编译的一种工具链，用来预编译以mips CPU指令集的so文件。

查阅资料发现：Google在新版本17.0.4754217的NDK中，删去了对mips指令集CPU预编译的支持，在预编译具有mips的so文件的项目时，就会报缺少文件或者目录的错误。

解决办法

1. 在gradle文件中配置打包参数，打包时排除/mips64/和/mips/文件下的所有so文件。

    packagingOptions {
        exclude 'META-INF/rxjava.properties'
        doNotStrip '*/mips/*.so'
        doNotStrip '*/mips64/*.so'
    }

2. 第二种：

删除/mips64/和/mips/文件下的所有so文件

第三种：

将SDK中的NDK回退到16b版本，去这里下载16b版本的ndk文件
https://developer.android.com/ndk/downloads/older_releases