About the Golang cross-compiling,say it simply that Windows build codes can run not only in Windows,but in Linux (Mac not test).
I work between Win and Linux,may I have build the code in Windows easy,but it in another pc maybe difficult.At least,you have to redownload the libs you use.And I have try the Cross-compiling.
In command or Terminal(installed golang >=go1.11.2),you can run “go version” to get your system’s info,save it and use it later.

Set Environment var
Windows:
in commmand : set var = value
Linux :
in terminal :export var = value

Keyin the command “go env” and find out the keys “GOOS”(windows,linux) and “GOARCH”(amd64 , arm).
If error with gcc,add up the gcc key ;
if error with CGO,set CGO_ENABLED=0 ;
if error with ‘cannot find package golang.org/x/sys/unix,git clone https://github.com/golang/sys.git to gopath’s golang.org/x/sys.

At last go build the code.

Example:
Windows(Windows's info:windows,amd64) build Binary executable file in Linux(Linux's info:linux ,arm):
keyin command

set GOOS="linux"  
set GOARCH="arm"  
set CGO_ENABLED=0  
set GOEXE=  
go build helloworld.go

Same infos,Linux build Binary executable file in Windows:

set GOOS="windows"  
set GOARCH="amd64"  
set GOEXE=.exe  
go build helloworld.go

Get helloworld.exe and run in windows;get helloword and run in Linux.

关于Golang交叉编译，简单地说，Windows构建代码不仅可以在Windows中运行，而且可以在Linux中运行（Mac不测试）。
我在Win和Linux之间工作，我可以在Windows中轻松构建代码，但在另一台PC中可能很难。至少，你必须重新下载你使用的库。我尝试了交叉编译。
在命令或Termial（安装golang> = go1.11.2）中，您可以运行“go version”来获取系统信息，保存并稍后使用。

设置环境变量
Windows:
命令行 : set var = value Linux :
终端 : export var = value

键入命令“go env”并找出键“GOOS”（windows，linux）和“GOARCH”（amd64，arm）。
如果gcc出错，请加上gcc键;
如果CGO出错，则设置CGO_ENABLED = 0;
如果错误'找不到包golang.org/x/sys/unix,就git clone https://github.com/golang/sys.git到gopath的golang.org/x/sys。

最后去构建代码。

例：
Windows（Windows的信息：windows，amd64）在Linux中构建二进制可执行文件（Linux的信息：linux，arm）：
键入命令

set GOOS ="linux"
set GOARCH ="arm"  
set CGO_ENABLED = 0  
set GOEXE =  
go build helloworld.go

相同的信息，Linux构建Windows中的二进制可执行文件：

export GOOS ="windows"  
export GOARCH ="amd64"  
export GOEXE = .exe  
go build helloworld.go

获取helloworld.exe并在Windows中运行;获取helloword并在Linux中运行