by ianremmler:

What does 'go version' print?

go version go1.3 linux/amd64

What steps reproduce the problem?
If possible, include a link to a program on play.golang.org.

http://play.golang.org/p/gQM33-crSr

Running go build will, about 15% of the time, produce a seemingly spurious error.

What happened?

ian@tau:~/devel/go/src/github.com/ianremmler/foobar% go build
# github.com/ianremmler/foobar
./foobar.go:31: cannot use f (type *C.foo) as type *C.struct_foo in argument to toGo
./foobar.go:32: cannot use gf.toC() (type *C.struct_foo) as type *C.foo in argument to
_Cfunc_foofunc

What should have happened instead?

No error.

Please provide any additional information below.

This is a pared down example based on a wrapper for the chipmunk physics library that I
forked and have been (mildy) maintaining:

https://github.com/ianremmler/chipmunk

The error did not occur in earlier Go versions.  The cyclically dependent C structs seem
to be implicated as the error goes away if the bar pointer is removed from foo, or vice
versa.