code review 6489075: doc: Don't imply incorrect guarantees about data races.

doc: Don't imply incorrect guarantees about data races.

A race between
        a = "hello, world"
and
        print(a)
is not guaranteed to print either "hello, world" or "".
Its behaviour is undefined.

Fixes issue 4039.

[dsymonds, 2012-09-04 01:18:29]

Hello golang-dev@googlegroups.com,

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

[r, 2012-09-05 14:53:02]

http://codereview.appspot.com/6489075/diff/5001/doc/go_mem.html
File doc/go_mem.html (right):

http://codereview.appspot.com/6489075/diff/5001/doc/go_mem.html#newcode274
doc/go_mem.html:274: <code>"goodbye, universe"</code>, or crash.)
regardless of the semantic change here, which i think is correct but not am not
certain about, the grammar is atrocious

[dsymonds, 2012-09-05 21:58:58]

https://codereview.appspot.com/6489075/diff/5001/doc/go_mem.html
File doc/go_mem.html (right):

https://codereview.appspot.com/6489075/diff/5001/doc/go_mem.html#newcode274
doc/go_mem.html:274: <code>"goodbye, universe"</code>, or crash.)
On 2012/09/05 14:53:02, r wrote:
> regardless of the semantic change here, which i think is correct but not am
not
> certain about, the grammar is atrocious

Alternatives welcome.

[r, 2012-09-05 22:46:44]

https://codereview.appspot.com/6489075/diff/5001/doc/go_mem.html
File doc/go_mem.html (right):

https://codereview.appspot.com/6489075/diff/5001/doc/go_mem.html#newcode274
doc/go_mem.html:274: <code>"goodbye, universe"</code>, or crash.)
Just fix the structure. Go back towards original structure, for instance:

It might print the empty string or crash; it cannot print...

[dsymonds, 2012-09-05 22:49:53]

https://codereview.appspot.com/6489075/diff/5001/doc/go_mem.html
File doc/go_mem.html (right):

https://codereview.appspot.com/6489075/diff/5001/doc/go_mem.html#newcode274
doc/go_mem.html:274: <code>"goodbye, universe"</code>, or crash.)
On 2012/09/05 22:46:44, r wrote:
> Just fix the structure. Go back towards original structure, for instance:
> 
> It might print the empty string or crash; it cannot print...

I don't think there's anything we can say it *won't* do, though. What about
this?

[dsymonds, 2012-09-06 22:58:41]

Russ, Dmitry: any thoughts on this?

[r, 2012-09-06 22:59:22]

https://codereview.appspot.com/6489075/diff/2002/doc/go_mem.html
File doc/go_mem.html (right):

https://codereview.appspot.com/6489075/diff/2002/doc/go_mem.html#newcode274
doc/go_mem.html:274: crash, or do something else.)
fine wording. i leave the semantic issue to others

[dvyukov, 2012-09-07 06:51:01]

Looks good

[gobot, 2012-09-07 17:22:33]

R=rsc (assigned by r)

[rsc, 2012-09-10 16:16:38]

LGTM

I believe this was a dreg from when strings were single-word values.

[dsymonds, 2012-09-10 22:48:13]

*** Submitted as http://code.google.com/p/go/source/detail?r=dbcfb4459ab8 ***

doc: Don't imply incorrect guarantees about data races.

A race between
        a = "hello, world"
and
        print(a)
is not guaranteed to print either "hello, world" or "".
Its behaviour is undefined.

Fixes issue 4039.

R=rsc
CC=dvyukov, gobot, golang-dev, r
http://codereview.appspot.com/6489075