cmd/vet: confuses C name with import "C"

[mvdan]

Please answer these questions before submitting your issue. Thanks!

What version of Go are you using (go version)?

go version devel +0e9d293db7 Sun Jun 11 04:25:26 2017 +0000 linux/amd64

Also on 1.8.3.

What operating system and processor architecture are you using (go env)?

Not relevant.

What did you do?

Run go vet on:

https://play.golang.org/p/uObdj6peim

What did you expect to see?

No vet errors related to passing pointers to C (I'm not even doing import "C")

What did you see instead?

$ go vet f.go
f.go:9: possibly passing Go type with embedded pointer to C
exit status 1

Note that this happens when the variable is named exactly C, and when we use a method on the type that has a pointer somewhere.

My intuition is that vet here does not check what C stands for. Since it seems like cmd/vet has type information, it should be fairly easy to figure out when C actually comes from import "C" and when it does not.

Happy to work on a patch if my thinking is correct.

[mvdan]

Looked at the code and this seems to be the case - only the ast.Ident is being used. CL incoming.

[gopherbot]

CL https://golang.org/cl/45551 mentions this issue.

[mvdan]

As per golang.org/s/owners, CC @robpike @josharian