编译springboot2.X源码时spring-boot-gradle-plugin报错

输入

mvn clean install -DskipTests -Pfast

后直接报错：

[ERROR] Failed to execute goal org.codehaus.mojo:exec-maven-plugin:1.6.0:exec (gradle) on project spring-boot-gradle-plugin: Command execution failed.: Process exited with an error: 1 (Exit value: 1) -> [Help 1] 

 根据下面提示，继续输入

mvn clean -rf :spring-boot-gradle-plugin