What version of Go are you using (go version)?

$ go version
go version go1.13.5 linux/amd64

What operating system and processor architecture are you using (go env)?

$ go env
GO111MODULE=""
GOARCH="arm"
GOBIN=""
GOCACHE="/home/summi/.cache/go-build"
GOENV="/home/summi/.config/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/home/summi/go"
GOPRIVATE=""
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/opt/go"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/opt/go/pkg/tool/linux_amd64"
GCCGO="gccgo"
AR="ar"
CC="gcc"
CXX="g++"
CGO_ENABLED="0"
GOMOD=""
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build687696122=/tmp/go-build -gno-record-gcc-switches"

I am under amd64 and I want to cross compile a dynamic library for arm. My document structure is as follows:
in GOPATH/src :
/demo
|----demo.go
/main
|----main.go

$ cat main.go
package main
import demo

func main(){
demo.Demo()
}
I have execute the command as follows:
$ export GOARCH="arm"
$ export CGO_ENABLED="0"
$ go install -buildmode=shared -linkshared std
$ go install -buildmode=shared -linkshared demo
$ go build -linkshared main.go

These produce libstd.so in $GOROOT/pkg/linux_amd64_dynlink, libdemo.so in $GOPATH/pkg and a binary file called main in $GOPATH/src.
However, when I put these 3 files on arm, the binary file called main can not be run because of file format error.
How can I cross compile the dynamic library for arm on my linux/amd64 computer???