Cross compilation fails

[rolandjitsu]

As reported in vmihailenco/taskq#55, if I try to cross compile a project that has a indirect dependency on this package I get:

❯ env GOOS=linux GOARCH=arm CGO_ENABLED=0 go build ./cmd/api/main.go                   
# github.com/valyala/gozstd
../../go/pkg/mod/github.com/valyala/gozstd@v1.6.2/stream.go:31:59: undefined: CDict
../../go/pkg/mod/github.com/valyala/gozstd@v1.6.2/stream.go:35:64: undefined: CDict
../../go/pkg/mod/github.com/valyala/gozstd@v1.6.2/stream.go:47:20: undefined: Writer

[valyala]

Try running the following command before building the app:

cd ../../go/pkg/mod/github.com/valyala/gozstd && make clean libzstd.a

This command should re-build libzstd.a file for the host GOOS and GOARCH as mentioned in the FAQ.

[rolandjitsu]

I managed to build it with a C cross compiler:

env CC=arm-linux-gnueabi-gcc GOOS=linux GOARCH=arm CGO_ENABLED=1 go build ./cmd/api/main.go 

But I could only do this on Linux. So I use docker to cross compile on a Mac.

I'm not sure if your suggestion would work if I do it on macOS and use the resulted binary on an ARM architecture.

[valyala]

I'm not sure if your suggestion would work if I do it on macOS and use the resulted binary on an ARM architecture.

My suggestion will work only when building binaries for host system. It doesn't work for cross-compilation :(

[rolandjitsu]

I'm not sure if your suggestion would work if I do it on macOS and use the resulted binary on an ARM architecture.

My suggestion will work only when building binaries for host system. It doesn't work for cross-compilation :(

That's ok, it can be done using docker, so that's good enough I'd say. I will close this issue, but maybe it's worth mentioning in the docs that one must use a C cross compiler and the appropriate flags when cross compiling.

[valyala]

maybe it's worth mentioning in the docs that one must use a C cross compiler and the appropriate flags when cross compiling.

Agreed. Could you prepare the corresponding pull request?