Vivado Synth -8 5535 报错解决办法

报错内容：

Synth 8-5535 Port <clkin> has illegal connections.it is illegal to have  a port connected to an input buffer and other compoents.

解决办法尝试：

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尝试方法如下

https://www.xilinx.com/support/answers/11076.html

完美解决！