cmd/go: Current 'go get' fails on some usages of 'import "C"'

[siebenmann]

On the current development git tip, an attempt to do 'go get -d github.com/derekparker/delve/cmd/dlv' fails for me with the following error message:

package github.com/derekparker/delve/cmd/dlv
    imports github.com/derekparker/delve/service
    imports github.com/derekparker/delve/service/api
    imports github.com/derekparker/delve/proc
    imports C: unrecognized import path "C"

I'm on 64-bit Fedora 22 Linux and I believe that this 'go get' is thus failing on the 'import "C"' in github.com/derekparker/delve/proc/breakpoints_linux_amd64.go. If I fetch the repo and so on by hand, I can do 'go install github.com/derekparker/delve/cmd/dlv' without problems; everything builds successfully. It's only the initial 'go get' that fails.

A run of git bisect reports that the first bad commit is af96030 'cmd/go: fix go get -u handling of changing dependencies', which at least appears to be a related change.

[gopherbot]

CL https://golang.org/cl/12322 mentions this issue.

[dmitris]

Having the same issue when trying to do: go get -v github.com/docker/docker/... with the Go beta version go1.5beta2:

$ GOPATH=/tmp/go go get -v github.com/docker/docker/...github.com/docker/docker (download)
package github.com/docker/docker/api/client
    imports github.com/docker/docker/autogen/dockerversion
    imports github.com/docker/docker/autogen/dockerversion: cannot find package "github.com/docker/docker/autogen/dockerversion" in any of:
    [$GOROOT]/src/github.com/docker/docker/autogen/dockerversion (from $GOROOT)
    /tmp/go/src/github.com/docker/docker/autogen/dockerversion (from $GOPATH)
import "C": import path does not begin with hostname
package github.com/docker/docker/api/server
    imports github.com/docker/docker/builder
    imports github.com/docker/docker/daemon
    imports github.com/docker/docker/pkg/graphdb
    imports code.google.com/p/gosqlite/sqlite3
    imports C: unrecognized import path "C"

[GeertJohan]

Having the same problem in go-gorp's travis-CI build with go tip.
https://travis-ci.org/go-gorp/gorp/builds/71365357

cc @nelsam

[ricsmania]

I'm also having this problem on Windows x64. x86 seems to be working.

[ianlancetaylor]

There is a patch out for review: https://golang.org/cl/12322 .

[btracey]

We are seeing this failure in gonum. It is currently passing on Go 1.4 and failing on 1.5beta2.

Pull Request: gonum/lapack#21
Travis Report: https://travis-ci.org/gonum/lapack/builds/73222462
Detailed Failure message: https://travis-ci.org/gonum/lapack/jobs/73222477

[btracey]

Oh, I see. This was fixed after beta2. Sorry.