GOOS=linux GOARCH=amd64 go build go build github.com/ethereum/go-ethereum/crypto/secp256k1: build constraints exclude allGo files in /Users/mac/Documents/project/src/github.com/ethereum/go-ethereum/crypto/secp256k1
Run the command with CGO_ENABLED=1 to enable the use of cgo when cross compiling.
CGO_ENABLED=1 GOOS=linux GOARCH=amd64 go build