code review 5868047: cmd/cgo: fix handling of errno for gccgo

cmd/cgo: fix handling of errno for gccgo

Fixes issue 3332.

[iant, 2012-03-21 16:53:32]

Hello golang-dev@googlegroups.com,

I'd like you to review this change to
https://go.googlecode.com/hg/

[bradfitz, 2012-03-21 16:55:28]

LGTM

On Wed, Mar 21, 2012 at 9:53 AM, <iant@golang.org> wrote:

> Reviewers: golang-dev_googlegroups.com,
>
> Message:
> Hello golang-dev@googlegroups.com,
>
> I'd like you to review this change to
> https://go.googlecode.com/hg/
>
>
> Description:
> cmd/cgo: fix handling of errno for gccgo
>
> Fixes issue 3332.
>
> Please review this at
http://codereview.appspot.com/**5868047/<http://codereview.appspot.com/5868047/>
>
> Affected files:
>  M src/cmd/cgo/out.go
>
>
> Index: src/cmd/cgo/out.go
> ==============================**==============================**=======
> --- a/src/cmd/cgo/out.go
> +++ b/src/cmd/cgo/out.go
> @@ -284,8 +284,13 @@
>                        }
>                        conf.Fprint(fgo2, fset, d)
>                        fmt.Fprintf(fgo2, "{\n")
> +                       fmt.Fprintf(fgo2, "\tsyscall.SetErrno(0)\n")
>                        fmt.Fprintf(fgo2, "\tr := %s(%s)\n", cname,
> strings.Join(paramnames, ", "))
> -                       fmt.Fprintf(fgo2, "\treturn r,
> syscall.GetErrno()\n")
> +                       fmt.Fprintf(fgo2, "\te := syscall.GetErrno()\n")
> +                       fmt.Fprintf(fgo2, "\tif e != 0 {\n")
> +                       fmt.Fprintf(fgo2, "\t\treturn r, e\n")
> +                       fmt.Fprintf(fgo2, "\t}\n")
> +                       fmt.Fprintf(fgo2, "\treturn r, nil\n")
>                        fmt.Fprintf(fgo2, "}\n")
>                        // declare the C function.
>                        fmt.Fprintf(fgo2, "//extern %s\n", n.C)
>
>
>

[iant, 2012-03-21 17:39:03]

*** Submitted as http://code.google.com/p/go/source/detail?r=15a98eba66e0 ***

cmd/cgo: fix handling of errno for gccgo

Fixes issue 3332.

R=golang-dev, bradfitz
CC=golang-dev
http://codereview.appspot.com/5868047