请教几个综合时的错误！

zrghost

这是几个综合时report的警告，请高人指点一下是什么意思，多谢了。
Warning: In design '123', there is 1 submodule connected to power or ground.
Warning: In design '123', there is 1 submodule with pins connected to the same net.
Warning: In design '123', there are 4 ports not connected to any nets.

raini135792

这几个问题应该看一下你的布线吧。好像是线路图出了问题。

zrghost

我还没做到布线这一步，这是由verilog直接综合时报的warning。不知是程序上哪里出了问题.