Missing import "C"? Please show a complete program.

@cznic I can repo with the following and any c type as the variadic arg.

package main

import "C"

func free(...*C.char) {
}

func main() {}

I can reproduce the issue with the above code in Go1.10. I don't know why it fails. I seem to recall, that Go cannot call C variadic functions but I cannot find that mentioned in the CGO docs at https://golang.org/cmd/cgo/.

However, in this case free is not a C function and I don't see why it should not compile.

cc @ianlancetaylor

I seem to recall, that Go cannot call C variadic functions but I cannot find that mentioned in the CGO docs at

@cznic is this the issue that you are looking for #975?
#23537 was filed to document this but the CL https://go-review.googlesource.com/#/c/90415/ hasn't yet been reviewed.

Although perhaps this is an entirely different issue. #975 is about calling variadic C functions in Go, while this is one is entirely failing when a Go function has a variadic C. signature.

/cc @hirochachacha too

Change https://golang.org/cl/110159 mentions this issue: cmd/cgo: parse cgo type inside ellipsis node

Thank you all guys for addressing this issue. Looking forward to using Go1.11 instead. Cheers!