code review 6862051: cmd/ld: skip 0-length write in cwrite

cmd/ld: skip 0-length write in cwrite

The 0-length part is fine, but some callers that write 0 bytes
also pass nil as the data pointer, and the Plan 9 kernel kills the
process with 'invalid address in sys call' in that case.

[rsc, 2012-12-06 05:00:17]

Hello ken2 (cc: golang-dev@googlegroups.com),

I'd like you to review this change to
https://code.google.com/p/go/

[rsc, 2012-12-06 05:00:29]

*** Submitted as https://code.google.com/p/go/source/detail?r=e2d1e2a9e609 ***

cmd/ld: skip 0-length write in cwrite

The 0-length part is fine, but some callers that write 0 bytes
also pass nil as the data pointer, and the Plan 9 kernel kills the
process with 'invalid address in sys call' in that case.

R=ken2
CC=golang-dev
https://codereview.appspot.com/6862051

[lucio, 2012-12-06 06:24:19]

Russ, shouldn't you let the "less than zero" potential error be
intercepted by the invocation of write() lower down?

Lucio.

[rsc, 2012-12-06 06:24:24]

On Thu, Dec 6, 2012 at 12:07 AM, Lucio De Re <lucio.dere@gmail.com> wrote:
> Russ, shouldn't you let the "less than zero" potential error be
> intercepted by the invocation of write() lower down?

I'm not worried about it. -1 would probably result in write returning
-1 so it wasn't getting caught before anyway.

Russ

[ken3, 2012-12-06 11:08:49]

lgtm