This one looks quite bad. I think it's caused by us not shipping the right '.a'
files. I've only started noticing this recently (and it's compounded with some
other issues I've observed with things like "go/ast" not being detected by the
go compiler). The error looks like (from an example umoci build):

% go build  -buildmode=pie -ldflags "-s -w -X
main.gitCommit="5ede8cd5c320360df6e39c669782f18eba09ddd7-dirty" -X
main.version=0.3.1+dev" -tags "" -o /dev/null
github.com/openSUSE/umoci/cmd/umoci
# internal/poll
/usr/lib64/go/1.9/src/internal/poll/fd_mutex.go:194:6: missing function body
for "runtime_Semacquire"
/usr/lib64/go/1.9/src/internal/poll/fd_mutex.go:195:6: missing function body
for "runtime_Semrelease"
/usr/lib64/go/1.9/src/internal/poll/fd_poll_runtime.go:17:6: missing function
body for "runtimeNano"
/usr/lib64/go/1.9/src/internal/poll/fd_poll_runtime.go:19:6: missing function
body for "runtime_pollServerInit"
/usr/lib64/go/1.9/src/internal/poll/fd_poll_runtime.go:20:6: missing function
body for "runtime_pollServerDescriptor"
/usr/lib64/go/1.9/src/internal/poll/fd_poll_runtime.go:21:6: missing function
body for "runtime_pollOpen"
/usr/lib64/go/1.9/src/internal/poll/fd_poll_runtime.go:22:6: missing function
body for "runtime_pollClose"
/usr/lib64/go/1.9/src/internal/poll/fd_poll_runtime.go:23:6: missing function
body for "runtime_pollWait"
/usr/lib64/go/1.9/src/internal/poll/fd_poll_runtime.go:24:6: missing function
body for "runtime_pollWaitCanceled"
/usr/lib64/go/1.9/src/internal/poll/fd_poll_runtime.go:25:6: missing function
body for "runtime_pollReset"
/usr/lib64/go/1.9/src/internal/poll/fd_poll_runtime.go:25:6: too many errors

These magic "runtime_*" functions are actually defined inside the runtime/...
source code, and should be shipped as .a files (from what I can tell).