What steps will reproduce the problem?

Make a package foo. Make a test in foo that imports a package bar. Add a compile error
to bar.

In your editor, make your build step:

go test -i -c foo

When this works, you know that your test is ready to run.

What is the expected output?

+ go test -i -c foo
# bar
src/bar/bar.go:3: undefined: net

What do you see instead?

+ go test -i -c foo
# bar
src/bar/bar.go:3: undefined: net
warning: building out-of-date packages:
    bar
installing these packages with 'go test -i foo' will speed future tests.

# bar
src/bar/bar.go:3: undefined: net

Which compiler are you using (5g, 6g, 8g, gccgo)?

6g

Which operating system are you using?

linux

Which version are you using?  (run 'go version')

go version devel +02e5cb24c95a Tue May 28 17:59:10 2013 -0700 linux/amd64

Please provide any additional information below.

Related to issue #3104 maybe.