$GOPATH/pkg is not mounted in the xgo container

[tamird]

...preventing any reuse of previous build artefacts.

I'm not sure if you want to do something implicit like what's currently done with GOPATH/src or something explicit like passing a flag that points to the shared pkg directory on the host machine.

Either way, this would save us about 10 minutes in our CI build.

[karalabe]

The reasons I didn't allow this is

• I wanted xgo to be sandboxed from the operating system so it doesn't overwrite something on your real GOPATH unexpectedly. E.g. building a different branch of a package in xgo would overwrite your workspace, and introduce weird anomalies in your dev environment.
• I wanted xgo to be stateless in that it only operates on the source code. If I were to allow reusing previous artifacts, it would open up a whole new can of worms with potentially linking in objects that were build from a different source. Currently I have reproducibility guarantees, albeit indeed at the cost of extra compilation time.

However I do feel your pain, and I think having an explicit flag to use some host side build cache could be a viable and clean enough solution. I'll think about the implications a bit and if I don't find anything too serious I'll try to add it as a feature :)

[tamird]

Any movement on this?