• I have searched the issues of this repository and believe that this is not a duplicate.
• I have checked the FAQ of this repository and believe that this is not a duplicate.

Environment

• Dubbo version: 2.6.2
• Operating System version: Win7
• Java version: 1.8

Step to reproduce this issue

不支持同时存在一个异步引用和一个同步引用，dubbo注入两个对象的地址都是相同的，第一个如果是异步则两个都是异步。 第一如果是同步则两个都是同步

@Reference(async = true)
private DebugService ansyncDebugService;

@Reference(async = false)
private DebugService debugService;